Current Conditions at Sanborn Field

 

Thursday Night: Showers. Low: 41

 

      

Friday: Rain. High: 46

 

Friday Night: Showers. Low: 40

Saturday: Rain then clearing. High: 56

Saturday Night: Chances of showers increase. Low: 37

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

Cloudy and rainy conditions remain the trend to finish out the rest of our week. By the weekend, more rain is expected with totals possibly exceeding over an inch!

-Labit 

 =================================================================

Forecasters: Labit, Easter

Date Issued: 03/23/2023 5:00PM CDT

Technical Discussion:

 

The primary focus of this forecast will be the continuation of rain as we go into the rest of this week and into the weekend. When comparing current observations and the track of the cold front, the NAM has positioning, strength, and surface temperatures more accurately depicted than the GFS hence why we're using the NAM for this forecast.

A 250mb jet streak located near the Great Lakes is funneling high levels of divergence aloft into south-central Missouri late Thursday night into early Friday morning. During this same time-frame, a shortwave associated with a low-pressure system located near Kanarado, will move across this region providing lift and circulation to support the production of heavy rainfall in southern Missouri. Complete saturation at 700mb stays south of our forecasting region, the same is true at 850mb leaving us dry until moisture advects north into both the upper and lower levels by Friday afternoon. Lighter rainfall will be the result of this moisture for central Missouri and will continue throughout Friday night into Saturday. 

 

By Saturday 06z the low-pressure system will migrate into central Missouri bringing with it ample amounts of lift and circulation. As a result, this will intensify rainfall to more moderate rates. Moderate rainfall will continue until around 15z when the low moves northeast into Illinois and Indiana. SREF plumes average out approximately 1.25" of rainfall in our region while areas more south could see rainfall totals exceeding 3"+. Moisture will still remain in our region providing clouds extending past our forecasting range.

A note to future forecasters, rain chances return as a result of another low-pressure beginning to move into Kansas pushing moisture southeast into our area.

  

-Labit & Easter

 

 Current Conditions at Sanborn Field

 

Thursday: Light Rain. High: 55

 

      

Thursday Night: Showers. Low: 41

 

Friday: Rain. High: 46

Friday Night: Showers. Low: 40

Saturday: Scattered showers in the morning. High: 54

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

Our rain streak will continue until Saturday. Most of the rain will be limited to showers; however, on Friday we can expect moderate rainfall. Don't forget your raincoat or umbrella!

-Samson 

 =================================================================

Forecasters: Hefner and Samson

Date Issued: 03/23/2023 10:00AM CDT

Technical Discussion:

  

Rain will continue to be Columbia's biggest "issue" throughout this period, as we will continue to see showers from today until Saturday. For this forecasting shift, the 12Z run of the GFS model was used due to a more accurate moisture profile correlating to real-time observations compared to the moisture-rich NAM models.

Beginning at the 300mb-level, there is a trough, with no tilt, situated over the southwest United States connected to a low-pressure system centered over the northwest Four Corners region. The trough and associated low will deepen and amplify as they move eastward. The trough will tilt negatively at 21Z Thursday and begin to affect Columbia at 00Z Friday by increased upper-level divergence from 00Z Friday until 12Z Saturday, signifying low-level convergence. The trough's negative tilt indicates that the weather system is strengthening. This strengthening correlates with the amplification of the trough. There will be a powerful jet streak near the right entrance region which will aid upper-level divergence. Additionally, due to the jet streak being located on the right side of the trough, both it and the associated low will begin to deamplify as it passes through the mid-Mississippi Valley, eventually entering the Great Lakes region, where it will eventually die, leaving Columbia in zonal flow.

At the 500mb-level, spotty amounts of circulation occur over Columbia for the forecasting shift; however, a vorticity maximum will go over Columbia at 03Z Saturday, lasting until 21Z Saturday. This maximum is associated with the low-pressure system noted in the 300mb-level analysis, and the circulation will move out towards the Great Lakes region with the low. The resolved circulation will aid in vertical forcing in the atmosphere, which can play a role in precipitation intensity.

Relative humidity values at both the 700mb- and 850mb-level indicate a dry layer starting at 12Z Thursday, and an increase in moisture will begin at 21Z Thursday. However, a dry pocket of air remains over Columbia until 12Z Friday, which can create a brief pause in precipitation. The high moisture values (>65% relative humidity) will persist over Columbia, eventually drying out at 21Z Saturday.  If the moisture at this level reaches saturation, thanks to high negative Omega values, precipitation will occur, and the precipitation intensity will depend on forcing at this level. For the 850mb-level, high moisture values resolved except for one time period, 15Z Saturday, where there will be a brief dry pocket before returning to moist air. So, cloud cover and precipitation support will be present at the 850mb-level for almost the entire period.

These high negative Omega values correlate with high moisture values at the 700mb level at 18Z Friday until 03Z Saturday and again at 09Z Saturday until 15Z Saturday. The negative Omega seen from 03Z Saturday to 09Z Saturday is in conjunction with the vorticity max noted at the 500mb-level. This coupling of forcing mechanisms could lead to more intense precipitation at that time period. However, the highest Omega values are expected to occur on Friday at 18Z, and this lifting mechanism will cause the highest intensity of our expected rain for this time period.

Down at the surface level, cold FROPA occurred earlier than previous forecasting shifts expected. FROPA resulted in a rapid decrease in surface temperature which sparked our significant 10-degree change in the forecasted high for today. Surface winds have a mostly northerly component, combined with solenoids throughout the entire forecast period, CAA is anticipated. As a result, the CAA will bring us temperatures down into the 40s. Additionally, a mid-latitude cyclone will begin to affect the Columbia area around 00Z Saturday. The most significant impact of this cyclone will be on wind direction for Columbia. Columbia's position relative to the front will cause a westerly shift in winds. The cyclone, however, should not cause Columbia to experience more precipitation. The reason for this conclusion, is that the cyclone will be too far east of Columbia for any precipitation associated with the cyclone to have an effect.

Wrapping up this AFD with sounding analysis, GFS generated soundings resolved the heaviest precipitation occurring at 18Z Friday. Negative Omega values are the highest at this time period, and the atmosphere is saturated (dewpoint temperature is equal to air temperature) up until ~680mb-level. The atmosphere is also close to saturation until around the 200mb-level, indicating the presence of moisture far into the upper atmosphere.

Precipitation totals from now until Saturday are from 1.25" to 1.5". This was determined using SREF plume guidance and sounding analysis. 

-Hefner and Samson 

 Current Conditions at Sanborn Field

 

Wednesday Night: Rain and scattered thunderstorms. Low: 61

 

      

Thursday: Cloudy with light rain. Dry time during the afternoon. High: 65

 

Thursday Night: Scattered showers. Low: 41

Friday: Rain. High: 46

Friday Night: Scattered showers. Low: 40

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

Rain chances persist through the end of the week with scattered thunderstorms expected overnight. Thursday will morning rain with plenty of afternoon dry time. Be prepared for rain throughout the day on Friday with temperatures staying in the lower to mid 40s.

-Chirpich 

 =================================================================

Forecasters: Cook and Chirpich

Date Issued: 03/22/2023 5:00PM CDT

Technical Discussion:

 

With Spring finally here, rain is dominating our forecast period. There exists a possibility for thunderstorms Wednesday night into Thursday morning. Rain is also likely Thursday evening, continuing through Friday and into Saturday. The rain will be associated with a low-pressure system that will pass over our CWA Friday night. The 12Z run of the GFS was used for this forecast, due to the forecast temperatures of the GFS more closely resembling the current conditions observed at Sanborn Field at the time of forecasting. 

The aforementioned low-pressure system, currently located over Colorado, is digging a trough over the western half of the CONUS. This has caused a ridge to build in over mid-Missouri that will quickly be forced east as the trough moves closer to Missouri. Ahead of the western low-pressure system, there is a surface low-pressure system that will be the driving force behind the storm potential for Wednesday night into Thursday morning. On Thursday morning, there is limited divergence modeled at 250mb, so it will not be the main factor supplying the forcing for this system. Rather, a FROPA associated with the low-pressure system is the predicted source of lift needed to support thunderstorm development. However, the FROPA isn't expected until late morning. Model soundings indicate that the mid-level lapse rates are greater than 6.5°C/km for all of Thursday morning, indicating that the atmosphere is particularly unstable for this time period. Moisture, another ingredient required for possible storms, is lacking Wednesday night at 700mb. However, moisture is seen at 850mb. The LLJ is also notably strong overnight on Wednesday, allowing increased moisture transport into the forecast area.

After consulting soundings, a clearer picture is formed regarding the incoming system. On Wednesday night, CAPE values near 900 J/Kg are accompanied by CIN values ranging from 0-100 J/Kg. This signals a weak cap, not allowing much energy to build up within a thunderstorm. However, various severe weather indices exhibit a possibility for severe weather, with a maximum Lifted Index of -4 signaling marginal instability and a maximum Total Totals value of 53 pointing to widely scattered severe storms. SWEAT values are also increased, further supporting the possibility of a severe thunderstorm. But, omega values are low throughout the entire passage of the system, leaving the cold front as the main source of lift for the system. There is also a significant dry layer in the mid-levels that never fully disappears, hindering deep saturation of the atmosphere.

Due to the above indices having varying levels of disagreement on the certainty of severe weather, a cap that is basically nonexistent, and lack of substantial moisture and lift, severe weather is not expected for tonight. There likely won’t be any issues, but it cannot be ruled out. Forecast confidence regarding severe weather is moderate, as a change in the timing of the FROPA could cause enough lift to aid in convection if it passes earlier in the morning. But, at this time, severe weather is not expected. 

After the FROPA Thursday morning, the area will be left with light rain as the mid-level dry layer persists. The passage of the cold front Thursday will hinder any temperature warm up on Thursday, and allow for much cooler temperatures for Friday. Model soundings show low level saturation from midday Thursday through midday Friday, at which the saturation is modeled to deepen, suggesting an increase in the rate of rainfall. This deepened saturation persists, into the afternoon, and subsides in the early evening Friday. after this, low level saturation persists throughout the remainder of the forecast period, suggesting light rain or drizzly conditions for Friday night into Saturday morning. Precipitation totals for the entire system are forecast to range from 0.5” to 1” of rain, with locally higher amounts possible. 

The passage of the low pressure system Thursday night into Friday morning will be causing issues for states to our south, such as Arkansas, Tennessee, and Mississippi. With a screaming LLJ providing ample moisture, Significant divergence signatures at 250mb along with strong vorticity and vertical velocity signatures at 500mb and 700mb respectively, and an unstable atmosphere shown by model soundings, all modes of severe weather are possible for these states on Friday. If the track of this low shifts northward, these issues could become our issues. Future forecast shifts should continue to monitor the track of the low as it approaches our CWA later this week. 

 

-Chirpich, Cook 

 

 

 Current Conditions at Sanborn Field

 

Wednesday: Morning showers. High: 72

      

Wednesday Night: Possible thunderstorms with scattered showers. Low: 64

 

Thursday: Scattered Showers. High: 65

Thursday Night: Rain. Low: 41

Friday: Scattered showers. High: 51

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

It is looking to be a wet week for mid-Missourians with expected rain every day to end the work week. Morning showers on Wednesday are followed up by cloudiness and possible overnight Thunderstorms. Thursday's scattered showers will not accumulate to much until the overnight hours. Friday, again, scattered showers with low accumulations. Total accumulations throughout the forecast period is around half an inch.

-Ritsema

 =================================================================

Forecasters: Ritsema, Clark, Cochran

Date Issued: 03/15/2023 10:00AM CDT

Technical Discussion:

 

 

Problem of the Day:

 

Possible thunderstorms accompanied by hail Wednesday night. Forcing for these storms include: a band of vorticity moving northeast through mid-Missouri between 00z and 12z Thursday, slight omega overnight with a max at 09z, a low-level jet with values exceeding 60 kts, and most unstable CAPE values exceed 900J/kg between the hours of 00z and 15z. In addition, low moisture content in the upper atmosphere accompanied by strong omega values suggests strong updrafts and the formation of small hailstones reaching the ground, if any reach at all.

 

At the 300mb level, an intensifying trough is traversing its way across the CONUS. As it moves into Missouri, no upper-level divergence is present during the night Wednesday into the early hours Thursday, but small shortwaves account for divergence over mid-Missouri at 00z Friday. The trough then transitions into a slight negative tilt bringing raised divergence levels in southeastern Missouri and along the Mississippi River, missing mid-Missouri. 

 

A band of shortwave vorticity moves northeastward through Missouri on Thursday between 00z and 12z, aiding in the thunderstorm formation overnight. Vorticity max appears northeast of the CWA in northeast Missouri and west-central Illinois. Friday at 00z, shortwaves move through mid-Missouri accounting for spotty, yet strong, vorticity values in mid-Missouri before moving southeast. Due to the trough, raised vorticity values will persist throughout the forecast period. 

Again, slight omega exists overnight Wednesday assisting in the formation of thunderstorms, yet no moisture exists at the 700mb level until Thursday 21z moving out by Friday 21z. Mid-Missouri will experience spotty omega which will account for higher QPFs Friday morning. 

A strong low-level jet from the southwest is situated over Missouri bringing warm moist air into the region. This jet strengthens a considerable amount overnight Wednesday with values exceeding 60 kts for a large portion of west-central Missouri. The jet diminishes, though, and winds slow down to less than 30 kts by Thursday 18z. The 850 mb level is saturated from Wednesday 15z to Thursday where it briefly dries out for a couple of hours in the morning, only to re-saturate for the rest of the forecast period. 

The track of the surface low is non-uniform as it passes over Missouri, but the track appears over southern Missouri moving east northeast. Although mid-Missouri is located to the northwest of the low center, no frozen precipitation is expected with this storm as surface temperatures are reaching into the upper 60s Wednesday and Thursday. The surface is saturated throughout the entire period suggesting low-level cloudiness throughout the end of the week. Ensemble models of 3-hour QPF outputs show heaviest rainfall will occur overnight Thursday into Friday morning, and expected accumulations are between half an inch to an inch of rain falling throughout the forecast period. 

-Ritsema 

 

 

Current Conditions at Sanborn Field

 

Tuesday Night: Scattered showers. Low: 42

 

Wednesday: Scattered Showers. Chance for t-storms. High: 72

Wednesday Night: Scattered showers. Low: 63

Thursday: Scattered showers. High: 70

 

Thursday Night: Thunderstorms likely. Low: 41

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

Rain rain rain. Oh, and more rain. Lots of rain this week so bring your umbrella with you every day. High temperatures will be in the low 70s Wednesday and Thursday in conjunction with this rain. Most of the time the rain will be light but could be stronger Wednesday morning and thunderstorms are likely Thursday night. Some of these storms could become severe so keep an eye out on the weather as you go about your evening.

-Smitty

 =================================================================

Forecasters: McCormack, Peine, Smith

Date Issued: 03/21/2023 5:00 PM CDT

Technical Discussion:

  

The 18z GFS model was utilized for this forecast as the 18z NAM was inaccurate with current surface temperature observations as well as the placement and timing of synoptic scale features. We are tracking multiple chances for rain from now until Friday morning with the potential for scattered showers and thunderstorms, especially Wednesday night into Thursday morning. Also, rain is likely for our area Thursday night into Friday with higher rainfall totals expected to be near southeast Missouri.

 

At 250mb, near-zonal flow exists across much of the CONUS which has kept temperatures in the mid-40s this afternoon. However, this pattern will begin to change as an upper-level trough begins to develop over the western United States overnight tonight and into tomorrow, amplifying our flow aloft to include a more southwest component. Even though precipitation is beginning to exit in Missouri, cloud cover will continue to remain overhead tonight as a warm front will lift north into the region Wednesday morning, advecting more moisture from the Gulf of Mexico. The best chance for showers and thunderstorms late Tuesday night will be north of our area as the warm front begins to situate across northern Missouri. A few rain showers are possible for mid-Missouri as we are just to the south of the warm front, but accumulation will likely be below 0.1” overnight. With surface winds out of the south-southeast around 10kts and stratus clouds for the entire night, temperatures Tuesday night will gradually warm up overnight and be near 50 degrees Wednesday morning. 

For Wednesday, the upper-level trough will continue to be more pronounced over the western CONUS and help advect significantly warmer air out of the southwest. Even with cloud cover still present due to the stalled front over the Missouri/Iowa border, temperatures will be 10-15 degrees above average (avg. high 58) Wednesday afternoon as 850mb winds are out of the southwest at 35-40 kts. Dew points will rise into the upper 50s and low 60s during this time and surface-based CAPE values are forecasted to be between 1000-1500 J/kg. However, capping is expected to be strong enough to prevent much from firing. Expect mostly cloudy conditions on Wednesday with a slight chance for a pop up thunderstorm. 

With stratus clouds continuing to dominate the central CONUS and southwesterly flow aloft down to the surface, Wednesday night low temperatures will be 20-25 degrees above average (avg. low 37). With the trough slowly developing over the desert southwest, our focus shifts to a broad surface low that begins to form east of the Rocky Mountains. Associated with the aforementioned low, a cold front will push southward from northern Missouri, allowing our surface winds to be more out of the west late Wednesday night into early Thursday morning. This setup is slightly more favorable as dew points will once again be in the low 60s with surface-based CAPE values between 500-1000 J/kg. However, a forcing mechanism will be present closer to our area as the cold front is forecasted to move through central Missouri late Thursday morning. Furthermore, the aforementioned trough will exit the western CONUS and divergence aloft associated with it will shift east into portions of Missouri which would support rising air. A few pop up thunderstorms are possible out ahead the front early Thursday morning with the greatest concern being small hail possible with some of these storms. Rainfall totals are expected to be less than 0.1” as convection is expected to be short lived as well as lower dew point temperatures for our area after the frontal passage.

Thursday’s high temperatures will be determined by the timing of the cold front. Most models have the cold front to our south before the afternoon, so expect a morning high temperature in the mid 60s before northwesterly winds filter in on the backside of the front, advecting cooler air for northern and central Missouri. As the cold front continues to slowly drift south, a surface low pressure will develop near the Texas panhandle, ejecting warm moist air out ahead of it. As of now, southeast Missouri will be sandwiched between cooler air from the north and warmer air from the south, setting up a stationary front that will have plenty of Gulf of Mexico moisture to work with. This will begin to set up late Thursday evening and produce the risk of heavy rainfall during the overnight hours in southeast Missouri. As for our area, we are still expecting rainfall Thursday night, but rainfall totals should be between 0.25-0.5” due to the location of the stationary front and the brunt of the moisture being further south. Confidence is low with the location of where higher rainfall totals could be, so if the front shifts further to the north, then I would be more concerned with the possibility of flash flooding. However, most of the models have the heaviest rain south of I-44. With northerly winds and rain likely most of the night, low temperatures are expected to cool into the low 40s.

Future forecast shifts should monitor the position of the stationary front as  rain chances will continue for our area throughout the weekend because of this pattern.

-McCormack

Current Conditions at Sanborn Field

 

Tuesday: Rainy. High: 45

 

Tuesday Night: Scattered Showers. Low: 42

Wednesday: Cloudy, Scattered T-storms. A few may be severe High:70

Wednesday Night: Scattered T-storms. Low: 63

Thursday: Showers Possible, Otherwise Cloudy. High: 68

 

  

Thanks to IconArchive.com for the icons!

====================================================================

Discussion: 

Lots of rain is on the way! Spring time thunderstorms are beginning to start. Temperatures will stay above average as the week progresses. Temperatures will return to average after a cold front moves through Thursday afternoon.

-Meier

 =================================================================

Forecasters: Meier, Simmons

Date Issued: 03/21/2023 10:00 AM CDT

Technical Discussion:

 

Rain chances will be the biggest problem the area will face as the week progresses. The GFS was the main model used because it has been better with temperatures along with handling the times of frontal passages well. The NAM was off in terms of lower level moisture and frontal passage timing which is why we decided to not use it for the forecast.

 

Currently, a shield of stratiform rain off to the southwest will track towards us as the day goes by. This rain is supported by upper-level divergence associated with a shortwave. Vorticity advection ahead of the shortwave coincides with the rain that will move through. The LLJ becomes enhanced today over Arkansas and southern Missouri helping aid in moisture transport. Eventually, lower-level moisture will move out in the late afternoon. The rain expected today will be lighter which bringing rainfall totals to 0.06'' to 0.25". Temperatures will not drop off by much tonight as there will be lots of clouds and warm air advection still occurring overnight. 

On Wednesday, a warm front will move north through central Missouri at 18Z. Surface dewpoints reach into the 60s after the warm front passage, increasing the chances of severe weather. Wednesday is going to be mostly cloudy, however; drier air will be moving down from the upper-levels which could bring sun. If some clearing occurs, severe thunderstorms become more likely and the convective temperature may be reached. CAPE values were consistently reaching over 1000J. This coupled with LI values of more than -5 and a total-totals over 50 will bring a severe possibility. A strong LLJ forms overnight over central Missouri, which will aid in energy in storm development. Although this is not a likely event, severe weather remains marginal late Wednesday night.

On Thursday, an upper-level trough digs through the western 1/3 of the CONUS. This will help the formation of a strong jetstreak from kansas to Wisconsin. This jetstreak will bring central Missouri upper-level divergence Thursday evening. A surface cold front attached to a low passes through mid-day Thursday. With a convective atmosphere still present, showers will still be possible especially ahead of the cold front. Precipitation totals will be from a trace to 0.06''. The daytime highs will be dependent on the timing of the frontal passage, but consensus remains that the daytime high will be reached in the early afternoon. 

Although rain chances are lower during the day Thursday, signs point to another round of rain moving in Thursday night. While the axis of heaviest rain appears to stay to the south, the next forecast group should monitor any progressive northward shift of the precipitation.

-Meier