Current Conditions at Sanborn Field

Monday Night: Mostly Clear. Low: 35

Tuesday: Clear. High: 70

 

Tuesday Night: Starry sky. Low: 40

Wednesday: Abundant sunshine. High: 72

 

 

Wednesday Night: Intermittent clouds. Low: 39

 

   

Thanks to IconArchive.com for the icons! 

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Discussion:

   

 With Spring being just a few short weeks away, mid-Missouri will be getting its first taste of warmer weather this week. A large high pressure system will be making its way across the country throughout the week. With this, abundant sunshine and warm temperatures will be introduced, reaching into the lower 70s on Wednesday. The clear sky will give nighttime temperatures the opportunity to return to the seasonal average, dipping into the lower to mid 40s.

- Millsap

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Forecasters: McMullen, Millsap, Cochran

Date Issued: 2/28/2022 5:00PM CST

Technical Discussion:

 

The 12Z run of the NAM40 was chosen for this forecast. The NAM was mainly chosen for its forecast temperatures on the SREF plumes. The observed current temperature and the forecasted temperature were very similar, in addition to the observed temperature being much warmer than forecasted on the GEFS plumes. Both surface maps were fairly similar when compared to the current surface map. The main focus of this forecast will be the warming temperatures over the next couple of days. 

 

Mid-Missouri is currently between two jet streaks when looking at the 250-mb plot of heights, winds, and divergence. Zonal flow dominates the region except for a small shift to meridional flow caused by a jet streak passing to the north from around 7Z to 18Z Tuesday. After this small disturbance, zonal flow continues to dominate the Midwest for the remainder of the forecast period. At the very end of the forecast period, a ridge covering the western CONUS begins to progress toward Missouri. No upper-level divergence is expected over Columbia. 

The passage of a small band of vorticity over Columbia around 21Z today, seen on the 500-mb plot of heights and voriticty, is the majority of the circulation that the area will see for the forecast period. With the exception of some spotty circulation over Missouri from 04Z to 12Z Wednesday, brought in by the previous mentioned upper-level ridge, there will be no circulation over the area for the remainder of the forecast period. 

A band of moisture traverses over the northern Mississppi River Valley and Ohio River Valley on the 700-mb plot of heights and relative humidity, but Missouri will remain dry for the majority of the forecast period. 

On the 850-mb plot of heights, winds, and temperature, Missouri's winds meander between W and NW for the entire period, with no particular direction monopolizing between the two. A mass of cold air remains over the the far northern Midwest and NE CONUS. An area of high pressure passes near the Gulf Coast, dictating the wind directions through midweek. 

 

Warm air advection, as seen on the plot of MSLP and 1000-mb to 500-mb thickness, helps to warm Mid-Missouri up for the beginning of this week. Southerly winds, in addition to solenoids, are over the area through 12Z Tuesday. At this time a LPS passing through Iowa causes the winds to shift to the west. After this, a HPS also drifts through Iowa, shifting the winds to the north

about 06Z Wednesday and eventually southerly for the remainder of the forecasting period. When looking at soundings, Mid-Missouri will remain fairly dry. Soundings become more moist from 12Z Wed to the end of the forecast period, but not saturated enough for cloud cover .

Future forecasters should look to the upper level ridge forming over the western CONUS on Thursday.

-McMullen 

 

Current Conditions at Sanborn Field

Monday: Clear. High: 62 

Monday Night: Clear. Low: 35 

Tuesday: Clear. High: 70 

Tuesday Night: Clear. Low: 40

Wednesday: Clear. High: 70

   

Thanks to IconArchive.com for the icons! 

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Discussion:

   

Did the groundhog lie to us? A ridge of high pressure will move east throughout the week leading to above average temperatures that will sweep through mid-Missouri earlier this week. A clear sky will be expected as the high pressure system moves east across the Plains. Plenty of sunshine and light winds will help those temperatures warm up to a more spring-like feel.With minimal cloud cover, nightly temperatures will still have the ability to dip down to a more seasonable average.

 

-Baker

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Forecasters: Baker, Bongard, Gromada

Date Issued: 2/28/2022 10:00PM CST

Technical Discussion: 

 

For this forecasting period, it seems the weather will be quiet and on a warming trend for mid-Missouri. The model that was chosen for this shift was the GFS because of the cooler temperature output NAM was giving for this week. It seems the NAM was not handling the upper-level ridge as well as the GFS.

This morning, radiative cooling brought lows below freezing. Radiative cooling will bring lows tomorrow a few degrees above freezing before highs climb into temperatures about 5-10 degrees above average. The main issue for this forecasting shift is the warming trend we are entering this week due to upper-level ridging located over went CONUS as of Monday morning. As this ridge pushes east, this brings above average temperatures for mid-Missouri for Monday through Wednesday. Winds this morning at 12Z at 250mb are around 80 knots with an increase in divergence aloft. Winds shift northwest as the upper-level ridge pushes east. Winds stay between 50-60 knots leading up to Wednesday late afternoon. A line of vorticity is seen with a shortwave trough at 18Z Monday reaching from the Four Corners region to the Great Lakes region. This line of vorticity associated with high values pushes into the mid-Missouri region Monday at 21Z. There are no significant values of vertical velocity seen at 700mb, but located in the northern CONUS and southern Canada, an atmospheric river of moisture associated with the upper-level ridge starts to take form Tuesday at 15Z and lasts until the end of the forecast period. Despite seeing the line of vorticity and the atmospheric river to the north, mid-Missouri will see warmer and dry conditions throughout the end of the forecast period.

-Gromada

 

                                                    Current Conditions at Sanborn Field

 Friday Night: Mostly cloudy. Low: 16

Saturday: Partly sunny. High: 40

Saturday Night: Scattered clouds Low: 25

Sunday: Clear with sunshine. High: 49

Sunday Night: Clear and sunny. Low: 34

General Discussion: 

Don't put your snow boots away just yet! Icy roads are going to be a factor starting off this forecast but will melt away with temperatures warming up. This week we are officially going to be out of the winter weather watch pattern we've been going through the last few weeks because temperatures are getting warmer by the day. Clouds are going to be a small factor along with some moderate winds but nothing that'll cause rain because this forecast in going to be pretty clear and dry.

-Watts

Forecasters: Watts, Mcdonald, Ethridge, Travis

Date Issued: 2/25/2022 5:00PM CST

Technical Discussion:

The forecast for today focuses on temperatures warming significantly over the weekend, changing our current active pattern to one that is much more inactive. The GFS was primarily used for today’s forecast, as current surface conditions were initialized much better than the NAM. 

In the upper atmosphere, Missouri sits right in the middle of the jet stream, with jet streaks only looking to intensify over the region throughout the next 48 hours. Saturday, from 3z to 12z in particular could see some of the strongest flow in the entire CONUS, with strong winds and considerable divergence aloft. This flow will enable any patterns dictated by factors in the levels below to work at a more rapid rate. By Sunday the jet stream dips southward and out of the state, leaving us in a gap with a similarly strong flow to our north. Winds shift sharply to the north at this time, indicating that a somewhat formidable FROPA may be occurring. 

 

Underneath the powerful jet at 500 mb, conditions appear much more inactive. Steady and warm southwest winds continue all the way through Sunday 6z, when a strong line of vorticity in the form of a cold front passes through. Vorticity looks to be contained to only the front though, with none to be found immediately preceding or following the system. While this could signal a dip in overnight lows for Saturday evening/early Sunday morning, it appears unlikely that any precipitation will be found alongside it. Winds remain northerly after the passage, but resume a westerly component in the hours thereafter, indicating that the warming trend will only be paused temporarily. 

 

The GFS 700mb level shows relatively low levels of moisture in Missouri for the duration of our forecast period. States to the southeast of Missouri, as well as our Boot-heel region, will see a good amount of moisture during the weekend, but it does not look likely to make its way far enough north to affect Columbia.

At the GFS 850mb level, the cold air over the Great Plains is beginning to move back north and warmer temperatures are settling in. We won’t see the intense temperature increase we saw at the beginning of this week, but it will become warmer and milder throughout the weekend. Winds at 850mb also look mild and not likely to cause any major problems during this forecast period.

At the surface, a high-pressure system is currently dominating the Great Plains region. A low-pressure system begins to work its way toward Missouri overnight on Saturday, but it doesn’t have the strength needed to persist and fizzles out before arrival.

The GFS sounding tells a similar story as the models. No precipitation is currently expected for the forecast period, but we will have some cloud cover overnight Friday in the upper levels. Skies become mostly clear from Saturday through Sunday, with small areas of moisture occurring at varying levels throughout. No major weather-related problems are expected for the next few days.

-McDonald, Ethridge 

 

Current Conditions at Sanborn Field

Friday: Mostly cloudy, clearing some this afternoon. High: 28

Friday Night: High clouds after sunset. Low: 15

 

 

Saturday: Scattered high clouds. High: 40

Saturday Night: Scattered clouds. Low: 24

 

Sunday: Clear and sunny. High: 49

 

Thanks to IconArchive.com for the icons! 

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Discussion:

    

Wintry flurries will peter out as the morning continues and the winter system moves east out of our region. Be mindful of icy road conditions still present on some side roads. Low clouds will block some daytime warming today before the sky starts to clear a bit this afternoon. Some high clouds should persist through Saturday as Columbia experiences very light winds out of the southwest. Temperatures will be on the rise Sunday and into next week, closing out a calm weekend despite a weak cold front pushing through the Midwest Sunday morning. 

- Schneringer

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Forecasters: Schneringer, VanUnnik, Bongard

Date Issued: 2/25/2022 10:00AM CST

Technical Discussion: 

   

The NAM40 was used for this forecast, and GFS20 was consulted for more accurate temperature forecasting. The NAM handled the atmospheric flow and pressure systems better, while the GFS handled temperatures better. The main area of focus for this forecast is the weak cold front that will pass through mid-Missouri on Sunday morning, and how it will affect temperatures throughout the day.

The Midwest is captivated by a zonal flow aloft, while a positively tilted trough drapes over the western half of CONUS. This trough makes its way east, and the axis centers over Missouri on Sunday morning.

Strong circulation at 500mb is pulled into the area on Sunday morning, and behind it, a northerly wind shift; both being associated with the frontal system.

Moisture advects into mid-Missouri at 700mb on Saturday morning. This moisture sticks around all day and night, causing a cloudy sky, before the aforementioned trough dries out the area on Sunday morning. Precipitation from this system is not expected at this time due to a lack of moisture at the surface.

The 850mb map, along with soundings, can be used for a more precise timing of the cold front on Sunday morning, which is expected to be around 09z. However, due to the timing and the weak winds, this front should not impact Columbia's weather too much. After FROPA, Missouri is going to experience daytime heating, along with clear skies, and Sunday is looking to have a higher temperature than previous days.

CAA takes place on Friday, and on Friday night and Saturday, a closed high can be seen over Missouri. Cold air remains throughout the forecast period, but on Sunday night, WAA may take place. Future forecasters should see warmer temperatures early next week.

-VanUnnik

Current Conditions at Sanborn Field

Winter Weather Advisory until February 25, 12:00 AM CST

Thursday Night: Clouds clearing through the night. Low: 15

Friday: Scattered clouds in the afternoon. High: 32

Friday Night: Clear. Low: 17

Saturday: Increasing cloud cover throughout the day. High: 40

Saturday Night: Partly cloudy. Low: 24

 

Thanks to IconArchive.com for the icons! 

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Discussion:

    A Winter Weather Advisory remains in effect until 12 a.m. Friday for potential light ice and snow. Accumulations will be negligible but frigid temperatures and icy roads will spell out harsh conditions for the evening. Temperatures will also likely dwell below freezing through Friday even as sunshine returns, though the weekend promises a steady warmup. Highs will rebound to above average for more spring-like conditions; with the spring equinox only a month away, a respite from the winter chill may be on the horizon.

- Splater

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Forecasters: Noblitt, Splater, Vochatzer

Date Issued: 2/24/2022 5:00PM CST

Technical Discussion: 

     For our forecasting period, we compared the 18Z surface analysis from the NWS to the MSLP plots in both the GFS20 and NAM40. Both models followed fairly similarly to the analyzed map, solidly placing two highs on both sides of the Great Lakes as well as the low over Colorado. When comparing the plumes, both the GEFS and SREF were close to the recorded temperature, with the most recent SREF runs running slightly warmer and the mean GEFS running slightly cooler. Due to the close proximity of the models’ outputs, both the GFS20 and NAM40 were utilized for this forecasting period. The NBM was also included to help with temperature forecasting, and GFS and NAM soundings were utilized for cloud cover.    

    Beginning with the 300mb plot of heights, winds, and divergence, a large jet streak rests across the eastern half of the CONUS, extending northeast from Texas into the North Atlantic-Appalachian region. A shortwave trough will begin to push eastward into the jet streak, increasing the speed of the winds over Missouri at this level around 150 knots late Thursday evening. This will bring some divergence over northern Missouri. After the trough passes to our northeast, the jet streak still resides over much of the CONUS, with wind speeds setting over the Mid-Mississippi Valley to around 100 knots. This jet streak remains over our region until very early morning Sunday when a positively-tilted trough slides in from the northwest.

    Observing our 500mb plot of heights, winds, and vorticity, a large area of circulation can be seen moving across the Mid-Mississippi Valley as a LPS over southern South Dakota transitions northeast, forcing the shortwave trough across Missouri Thursday night. Following this passage, zonal flow remains in effect for our region until early Sunday morning, when the positively tilted trough forces its way into Missouri, bringing another large area of circulation before quickly continuing to our east.

    Following this up with the 700mb plot of heights, winds, omega, and relative humidity, a large band of saturation associated with the Low over South Dakota will move across northern Missouri Thursday night. However, little to no lift can be seen from the omega values, indicating the possibility of clearing clouds despite the saturation. This saturation travels on late Thursday night, leaving the sky over the Columbia region unsaturated until Friday evening. A large batch of saturation, residing with a LPS over the Rockies, begins to move toward the Mississippi River during this time. This moisture continues to travel across Missouri through the end of the forecast. Some lift can be seen in the omega values corresponding to the passage, indicating the chance of building cloud cover Saturday.

    Finishing up with the 850mb plot of heights, winds, temperature, and dewpoint, we can see a surface Low residing over Kansas City. Despite this forming southeastern winds for our region, a blanket of cold air extends far enough to our south that we will receive very little warming. This low swiftly moves northeast, exiting Missouri late Thursday evening. A westerly into northwesterly shift of our winds helps to keep our temperatures cool Friday. However, a surface High moving from Oklahoma into Arkansas will see our winds shift back to the west and into the southwest. The change in our winds is short-lived however, as the positively tilted trough snaps our winds back to the northwest for the remainder of the forecasting period. Looking at the surface plot of MSLP and 1000mb-500mb thickness, some very strong CAA can be anticipated over Thursday night into midday Friday. Little advection can be expected for the remainder of the forecast due to the lack of solid solenoids.

    Soundings indicated increasing and decreasing cloud cover throughout the forecasting period, however due to the lack of significant saturation near the surface or aloft no precipitation is anticipated after Thursday night, with only trace amounts expected.

    Future forecasters should keep a close eye on the LPS moving in from the Rockies Saturday.

 

- Noblitt

 

   Winter Weather Advisory until February 25, 12:00 AM CST

Current Conditions at Sanborn Field

Wednesday Night: Cloudy. Low: 18

Thursday: Overcast. Sleet in the early morning, changing to snow by mid-morning. Snow moving out by evening. High: 25

Thursday Night: Cloudy. Low: 15

Friday: Few clouds. High: 30

Friday Night: Clear. Low: 17

 

Thanks to IconArchive.com for the icons! 

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Discussion:

For the third week in a row, Mizzou sees potential for a snowy Thursday. Wednesday afternoon sees cold temperatures with wind chill and overcast sky conditions. As a low pressure system moves East from Colorado into Missouri, winter weather becomes a greater potential. The chances for precipitation greatly increase Thursday morning around 9am, where a sleet and snow mix is likely to fall. Sleet will quickly dissipate as temperatures continue to drop, and snow begins to become heavier around noon. The chance for snowfall continues throughout the afternoon into the early evening. The predicted sleet amounts to 0.5 inches and snowfall amounts to 1 to 3 inches for Thursday. Those who are driving should take caution and drive slow, as roads may be slippery throughout the day. Columbia will dry out as the system moves to the Northeast. Thursday night will begin to clear as cold air advection strengthens in Columbia. Friday will see sunshine as sky conditions begin to clear. There will be a few clouds in the early afternoon. A high pressure system moves over Missouri from the West setting up calm weather for the weekend. 

- Heienickle

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Forecasters: Meyer, Heienickle, Orr

Date Issued: 2/23/2022 5:00PM CST

Technical Discussion: 

 

For this forecast the NAM was used over the GFS for a variety of reasons. Many models vastly overperformed the temperatures today, putting central Missouri into the 20s when we remained in the 10s all day. However, the NAM was closer to our current temperature and had a better handle on the precipitation falling over southern Missouri while writing this forecast. Once we got to sounding analysis, both the NAM and the GFS were used to determine timing of precipitation and the specific time of changeover.

Beginning at the 250-mb level the jet stream is parked right over the central United States, with wind values between 90-170kts throughout the forecast period. Not a whole lot of divergence in the upper-levels with the exception of this evening.

Vorticity also remains focused to Missouri’s west and south, not fully entering the state until Friday as per 500-mb analysis. The trough associated with the vorticity ejects into Missouri around Friday at 00Z, and with it large amounts of circulation pass overhead.

The 700-mb analysis perfectly outlined the conditions in terms of RH and current precip. With the higher RH amounts focused near and south of I-44, that is where we find the precipitation falling so far. Columbia has been focused on the far northern edge of these higher RH values, but still too dry to see any precipitation. At 21Z on Wednesday, Columbia has remained snow-free but Jefferson City has at least a dusting signifying the cut-off of higher RH values. Higher RH values are absent over Columbia until 15Z on Thursday, meaning we likely will remain dry through the night until Thursday morning.

Soundings from the GFS and NAM reinforce the idea of the dry layer continuing through the night into Thursday morning. The GFS gets colder with the absence of any warm nose, while the NAM keeps a warm nose through the morning. While there is the possibility of sleet mixing in when precipitation begins around 12-15Z, any sleet is expected to switch to snowfall by 18Z. Snowfall amounts should be light with amounts ranging from 1-3”, while sleet amounts should remain less than .25".

At the 850-mb and the surface, a cold front can be identified stretching from Ohio into Oklahoma. This front stalls over southern Missouri through Thursday before moving away with the trough ejection. After the cold front begins to progress eastward, CAA moves in reinforcing the colder air already present over Missouri on Friday.

 

- Meyer

 

Current Conditions at Sanborn Field

 

Wednesday: Overcast. High: 25

 

Wednesday Night: Cloudy. Low: 22

Thursday: Wintry mix then snow. High: 28

 

Thursday Night: Snow ending before midnight. Cloudy. Low: 17

 

Friday: Clear. High: 30

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Discussion:

 

Are you beginning to wonder if mid-Missouri weather has something against Thursdays? We are too! In addition to bitterly cold temperatures, a wintry mix of sleet and snow is expected to begin on Thursday morning before transitioning into snow exclusively by early afternoon. Snowfall will come to an end by the late evening hours on Thursday with accumulations between 1 and 3 inches. Cloud cover will decrease as we move into early Friday morning, bringing us some much needed sunshine and warmer temperatures as we head into the weekend.

- Macko

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Forecasters: Kobielusz, Macko, Bongard

Date Issued: 2/23/2022 10:00AM CST

Technical Discussion: 

    The 06Z run of the NAM40 was chosen for this forecast. After examining both the NAM40 and GFS20, we concluded that both models were running warm; however, the NAM40 was better depicting low pressure over the four corners region and a high over the Dakotas. The placement of the low over the four corners is important because this low will be associated with the snowfall that we are expecting and the track of the low will be a factor in how much snow will accumulate, which is the biggest challenge of this forecast. Soundings and the National Blend of Models were consulted for forecasting p-type and timing of precipitation. In preparation for upcoming winter precipitation, the National Weather Service has issued a Winter Weather Advisory beginning at noon today.

A deep, positively tilted trough is located over the central Great Basin region. This trough will push east into mid-Missouri over the forecast period. Currently Missouri is under the influence of an upper-level jet streak making our upper-level winds upwards of 150kts from the southwest. Just before noon today, an area of upper-level divergence encapsulates Missouri, implying the existence of lower-level convergence. This divergence clears out overnight only to reform during the evening on Thursday only not as strong. The jet streak however, strengthens over mid-Missouri with upper-level winds at 170kts out of the west.

Vorticity in the mid-levels is currently null. The first time Missouri will see vorticity in this forecasting period will be tonight over the I-44 corridor, but it will be weak. A noteworthy amount of vorticity associated will the positively tilted trough will move into mid-Missouri Thursday night.

There is a small area of upward vertical motion engulfed in a larger area of downward vertical motion currently over the forecast area. Throughout the day downward vertical motion will remain dominate before the trough moves into central Missouri late Thursday night bringing with it a large amount of upward vertical motion in the same area as the vorticity. This leads us to believe that there could be the chance for some precipitation, but moisture in the mid-levels in mid-Missouri will be scarce until late morning on Thursday. This is not the case in southern Missouri where moisture is abundant. This will pose the question of whether-or-not Columbia will be seeing snow on Wednesday.

A low-level jet streak just to our south will bring in low-level moisture from the Gulf of Mexico, but our low-level winds will remain out of the north causing our surface temperatures to be well below freezing and air, dry. Low-level moisture will increase on Wednesday and will remain throughout the day on Thursday before clearing out early Friday.

With the existence of the dry layer in the mid-levels Wednesday, any precipitation is going to struggle to reach the surface. Columbia may see a few stray snowflakes, but accumulation is not expected. By mid-morning on Thursday the dry layer should become more saturated and sleet is expected to reach the surface as a warm nose barely goes above freezing. Sleet is expected to transition into snow by early afternoon as the warm nose dips well below freezing. Accumulations for sleet are forecasted to be around 0.5" and total snow accumulations are expected to be within the 1-3" range.


-Kobielusz

Current Conditions at Sanborn Field

 

Tuesday Night: Partly cloudy. Low: 16

 

Wednesday: Cloudy. High: 28 

Wednesday Night: Cloudy. Chance of flurries. Low: 22

 

Thursday: Cloudy. Snow likely. High:28

 

Thursday Night: Cloudy. Snow stopping early, becoming freezing rain/drizzle. Low: 17

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Discussion:

 

What a chilly "twos-day" this has been. Mid-Missouri has been steadily cooling off since a cold front passed last night, leaving us with northerly winds and a cooling trend that will continue through Tuesday night. The winds will keep flowing at about 15 mph from the northwest, forcing our temperatures into the mid-teens. Wednesday morning, the winds will slow to 5-10mph, and begin shifting to be northeasterly. The sky will become cloudier as the day progresses, capping our high temperature in the upper-20s. Sky conditions will become overcast overnight Wednesday, which will keep the low temperature in the lower-20s. Also, a low pressure over western Oklahoma will begin making its way eastward at this time. Due to the low pressure system, there is the opportunity to see some flurries after midnight, but we are not expecting much, if any, accumulation. Thursday will once again be interesting as snow, and possibly sleet, are expected to start falling around sunrise and continue throughout the day. Accumulation totals are expected to stay less than 2 inches. Thanks to the cloud cover, our high temperature will stay about 4 degrees below freezing. The winds will shift from the northeast to the northwest Thursday night as the low pressure moves into the southeast CONUS. The snow will transition to freezing rain/drizzle in the early evening and then stop around altogether midnight. Because of the winds shifting, we are expecting a cooler low (upper-teens) than the previous night.

-Alexander

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Forecasters: Alexander, Duff, Orr

Date Issued: 2/22/2022 5:00PM CST

Technical Discussion: 

    The GFS 12Z run was used in this forecast. Both the GFS and the NAM had a warm bias in forecasting surface temperatures, but the GFS matched up closely with upper level conditions. Soundings were used to diagnose precipitation type and timing of the event. The problem of the week and the focus of this forecast is similar to last week as an upper-level trough will bring snow and other associated wintry precipitation to the region late Wednesday and during the day on Thursday. 

    At 250-mb the flow of the atmosphere is very meridional, a positivity tilted trough sits over the Western CONUS and moves east during the forecast period. Winds at this level will increase as the jet stream rounds the base of the trough and a jet streak becomes centered over Missour. The streak intensifies around 21Z Wednesday, putting Columbia in the right entrance region indicating upper level divergence. A second jet streak approaches Mid-Missouri Thursday afternoon around 00Z Friday and strong divergence aloft is associated with the left exit region of the jet streak. 

    In the mid levels of the atmosphere, the trough is centered over the southwest and moves north east towards Missouri. At this level, circulations ahead of the trough begin 15Z Thursday, aiding in the development of precipitation. Vorticity intensifies around 03Z Friday, but due to lack of abundant moisture only supports cloud cover. Behind the passage of the trough the flow becomes more zonal and calmer conditions are expected. 

    Mid level relative humidity values begin to increase over central Missouri as moisture is advected from the south beginning 21Z Wednesday. A period of dry air at 700-mb and dry air at lower levels indicates that precipitation won't start until later Wednesday night, around 06Z Thursday, when moisture associated with the trough is advected into the area. Ample moisture until 06Z Fri will support cloud cover and precipitation. Clearing will begin after the precipitation ends early morning on Friday. 

At 850-mb a closed low pressure system moves off to the northeast overnight on Tuesday leaving behind colder air and a northwesterly wind. A col can be identified around 18z Wednesday. Winds die off as we are in the saddle point, but then switch to a southernly direction as a high pressure over Florida and a low pressure system to the southwest begin to dominate the flow at this level. The nose of the low level jet at 850-mb sits in southern Missouri but helps to saturate the region beginning 00Z Thursday. Winds will switch back to a northernly direction late Thursday.

    Sounding were helpful in the development of this forecast to diagnose precipitation type and timing of the event. A 03Z sounding from the GFS indicates ice from seeder clouds in the upper-levels of the atmosphere will help to saturate a dry layer in the mid-levels of the atmosphere. Moisture begins to increase at the surface level from 09Z- 12Z Thursday where periods of precipitation is possible. The likely precipitation at this time is freezing rain or drizzle, but will transition to snow after the atmosphere becomes fully saturated around 12Z Friday. Any precipitation will start to taper off around midnight Thursday. Early evening Thursday, snow will transition to freezing rain or drizzle, as the upper levels of the atmosphere dry out. The atmosphere will dry out from the top down leaving sufficient moisture in the lower levels for clouds and the potential for freezing rain or drizzle before the precipitation ends Thursday night. 

    Total precipitation accumulations are trace on Wednesday night and total snow accumulations are expected to be under 2 inches on Thursday. Potential impacts include hazardous road conditions. Future forecasters should pay attention to upcoming winter weather event. 

-Duff