Thursday, December 8, 2022

 Current Conditions at Sanborn Field



 
Thursday: Overcast. High: 50
 
 
 
 
Thursday Night: Rain. Low: 42
 
Friday: Morning Fog. Decreasing Clouds. High: 52
 
  
 
Friday Night: Mostly Clear. Low: 38
 
 
 Saturday: Rain. Low: 49

 

Thanks to IconArchive.com for the icons!


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

Discussion: 



Thursday’s rain is expecting to hold off until this evening and overnight into Friday, leaving us with an overcast but dry day. We may see some fog Friday morning, but conditions should clear and dry out throughout the day and overnight. Friday’s clearing sky will let us catch a glimpse of the sun before another round of rain on Saturday. Temperatures are expected to be relatively consistent over the next few days as they sit in the low 50s to upper 40s during the day and low 40s to upper 30s overnight.

-Sallot

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

Forecasters: Sausen, Sallot, Baker

Date Issued: 12/08/2022 12:48 PM CST

Technical Discussion:
 

Visible satellite observations show instability over Northern Arkansas. Elevated radar reflectivity over the same area indicates precipitation. RAP analysis shows moisture present over the CWA, but no forcing for necessary for precipitation, which explains the lack of rain so far today. Therefore, the possibility of rain showers Thursday evening into Friday will be the focus of this forecast.

Due to the uncertainty of rain throughout the forecast period, this forecast utilizes output from the HRRR, NAM12, and GFS20. The HRRR shows some precip over the CWA Fri 02Z to 07Z. At 250mb, the GFS shows divergence over the CWA Thurday 15Z and Friday 09Z. Both the GFS and NAM have the subtropical jet positioned over the CWA throughout the forecast period with zonal winds out of the west. The GFS shows more divergence over the CWA on Saturday 09Z in association with a east-moving shortwave trough.

There are scattered vorticity values at 500mb over the CWA on Thursday 00Z through Friday 00Z. A second band of vorticity associated with a shortwave trough passes over on Saturday 09Z to 18Z. The second band coupled with divergence at the 250mb level would provide adequate forcing for active weather.

At 700mb, the GFS shows significantly more moisture present over the CWA from Thursday 00Z through Friday 00Z, however the NAM still shows some moisture present in this time span. The NAM also shows negative omega values for Friday 00Z through 09Z, providing another lifting mechanism for moisture. Both the GFS and the NAM show another round of moisture on Saturday 09Z through 18Z which should provide ample cloud cover over the CWA.

A high pressure system situated near the Gulf of Mexico should bring warm moist air northward through the CWA on Thursday 06Z through Friday 12Z. Moisture transport vectors and resulting high RH values on both models also support this transport. Another round of high RH values will arrive Saturday 09Z into Sunday 00Z.

Surface winds increase to 10 knots out of the east Thursday 18Z but then make a rapid switch out of the west on Friday 15Z as a result of a low pressure system from the north moving eastward. Solenoids present from 00Z until 21Z Friday further indicate advection of warm, moist air into the CWA from the Gulf of Mexico.

GFS model soundings show near saturation from 400mb to the surface until 15Z Thursday, saturdation then progresses from the top down to the surface. K index values reach their maximum at 30, indicating a significant chance for rain showers. CAPE values are minuscule, however, so there is little thunderstorm potential throughout the forecast period. Lingering saturation near the surface displayed on the NAM sounding may also indicate the presence of fog Friday morning. Overall, many conditions are present for precipitation to occur Thursday evening into Friday morning.

-Sausen

Wednesday, December 7, 2022

 

 


Wednesday Night: Increasing Clouds. Low: 45
 
Thursday: Rain through the day. Cloudy. High: 47

Thursday Night:
Cloudy. Low: 45

Friday:
Morning Fog. Mostly Cloudy. High: 47

Friday Night: Cloudy. Low: 40

Thanks to IconArchive.com for the icons!


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

Discussion: 

Through the end of the week the cloud cover will persist and temperatures will remain in the upper 40’s for the forecasting period. The hot topic is the rain entering the CWA we will see Thursday morning and persist through the day ending late Thursday night. Finish the week strong and don’t forget those umbrellas for Thursday. 

-Jones

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

Forecasters: Cochran, Jones

Date Issued: 12/07/2022 6:30 PM CST

Technical Discussion:
 

This forecast was made using the GFS20 due to it starting off with better agreement in the placement and intensity of moisture with the 18Z surface map from the NWS. Thursday will bring rain into the CWA lasting through the day and tapering off Thursday night. To end the week, clouds and mild temperatures will persist until Friday. 

Upper-level maps have a trough northeast of Missouri, keeping the polar jet in our area with a jet streak over IA Wednesday night. Zonal flow will continue through the week until a LPS comes into the area Saturday at 12Z, finally pushing the jet stream to the east. Upper-level divergence enters the CWA at 09Z Thursday and will persist through the day. Vorticity, moving in from the SW, arrives early Thursday morning and persists until Friday 03Z.  

At the 700mb and 850mb a trough sitting over Colorado moves NE and passes through northern Iowa. This brings with it moisture from the SW that enters the area at 06Z Thursday and intensifies through the day. This paired with SFC convergence and upper-level vorticity allows for upward motion, bringing clouds and rain. As the LPS continues eastward, it takes the moisture out of the area around 06Z Friday. Another trough approaching from the west will bring less intense moisture into the area from the SW Saturday at 09Z.  

GFS soundings show the air will become more saturated this evening and into early Thursday morning as the midlevel moisture enters the region. Expect rain to begin around this time at 09Z. The rain will continue through the day leaving up to 0.50in before dissipating Thursday night as a HPS over KS kicks it out. SFC winds will be light at 10kt and shift from the east to the west, but our temperatures remain steady through the end of the week in the high 40s. Thursday night’s cloud cover keeps temperatures in the mid 40s, with slightly cooler temps on Friday night. 

Future forecasters should be on the lookout for more precipitation on Saturday as midlevel and surface level maps suggest rain could be possible. 

-Jones


 





Wednesday:
Mostly Cloudy. High: 50

Wednesday Night:
Increasing Clouds. Rain Late. Low: 42


Thursday:
Morning Rain. Clouds stick around. High: 49

Thursday Night:
Cloudy. Low: 45

Friday:
Chance for light morning rain. Mostly Cloudy. High: 47

 

Thanks to IconArchive.com for the icons!


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

Discussion:

Things look dreary for the last few days of classes! Finish strong Tigers! 

Temperatures will remain steady, with our highs and lows remaining in in the 40s and the chance for rain returns! A soaking rain is looking likely Wednesday night and Thursday morning as a weak system moves in from the southwest. A front moves through Friday morning bringing a slight chance for showers and falling temperatures throughout the day.

-Russell

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

Forecasters: Russell, Shaw

Date Issued: 12/07/2022 9:00 AM CST

Technical Discussion:
 

The remainder of the week looks to be rather deary and mild. Cloud cover is expected to stick through the week with a soaking rain tonight and tomorrow morning. For this forecast, we favored the GFS and EURO over the NAM due to consistency with timing of the the shortwave bringin our precipitation and low placement on Friday. 

In the upper-levels, the sub-tropical jet is situated overhead and just to our north placing is in a consistent westerly flow through the entirety of the forecast period. A weak shortwave trough is ejected from the Rockies Wednesday evening and moves northeast bringing an area of increased divergence to the forecast area early Thursday morning. As it exits to our northeast, the sub-tropical jet sags south before setting up directly overhead with strong southwesterly wind. In similar timing with the shortwave, we see an increase in vorticity 06z Thursday that slowly moves to our northeast. Following the Thursday event, we see a closed low develop near the KS/NE boarder. This system will remain to our north, but it does bring some weak vorticity Friday morning. At this level we can see the culprit for our current pattern, a large blocking high anchored over the gulf is locking the sub-tropical jet over the central US keeping us in this quasi zonal flow.

In the mid levels, that shortwave noted in the upper levels can be seen more clearly as it moved into the forecast area this evening. We begin to see increased moisture at the 700mb levels as our winds become southwesterly as opposed to the westerlys we are seeing now. This level is where the NAM differs greatest from the global models as it wanted to quickly move the closed low towards the Great Lakes, while global models agreed on it stalling over the Corn Belt. Towards the 850mb levels, we see our moisture stick around longer with humidity >90% this evening through early Friday morning. This paired, with the weak diffluent trough supports the idea for widespread slow moving precipitation to overtake the region 00z - 15z Thursday. Despite lower moisture at the 700mb levels, the weak cold front associated with the low over Iowa Friday morning does support the potential for some light rain showers.

At the surface, the air is already near saturation with temperatures in the 40s and dew points being only a few degree behind. A surface warm front associated the shortwave is gradually shifting north this afternoon. Where this front sets up will decide where the area of heaviest rain will fall and current indications suggest across the Ozarks. This will allow rain to develop along and just north of the front tonight into tomorrow. Overall, we expect .25" to .5" of rainfall with areas to our south potentially receiving upwards of 1" of rainfall. We then see a surface low develop off the mountain west and move into Kansas and then northwestern Missouri. This will aid in lifting the warm front north, allowing us to breifly warm Friday before a cold front quickly moves in. It should be noted, that with the weak southerly winds as the WF passes, we will see an increase in surface moisture as well. Assuming winds remain calm, dense fog remains a concern for Friday morning before the CF moves through the area. With the timing of the cold air Friday, we expect to hit our high temperatures early in the morning with temps cooling off throughout the day.

 

Tuesday, December 6, 2022







Tuesday Night:
Mostly Cloudy. Low: 39


 

Wednesday:
Partly Cloudy with clouds increasing. High: 50






Wednesday Night:
Rain Late. Low: 42
 

 


Thursday:
Light Rain. High: 49
 
 




Thursday Night:
Mostly Cloudy. Low: 41

 

Thanks to IconArchive.com for the icons!


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

Discussion:

Mid-Missouri is expecting a dreary week for the next few days as clouds will be enveloping the sky. Mild temperatures this week will persist with daytime highs in the 40s to near 50. You'll want an umbrella heading out the door Thursday morning as light rain will be falling until moving out Thursday afternoon.

-Simmons

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

Forecasters: Simmons, Meier, Macko

Date Issued: 12/06/2022 5:00 PM CST

Technical Discussion: 
 
For this forecast period both the NAM12 and GFS20 were used based on their agreement on the jet stream placement over the Central CONUS. Consistency with the surface low placement over northern Arkansas caused us to use a blend between both models for the disturbance later this week. This disturbance will allow for measurable rainfall starting Wednesday night into Thursday.

Starting Tuesday night, 300mb analysis shows the subtropical jet stream over Missouri with the polar jet over the Canadian/CONUS border. Westerly mid-level flow will continue tonight as low level saturation exits the area late tonight. The stationary front in southeast MO at 21Z is currently responsible for the lower stratus deck. As the low moves to the east, clouds will begin to diminish late tonight.

Wednesday will be calm between the current surface low exiting and an approaching shortwave in the West. The upper-level shortwave trough over the West Coast will traverse into the Mountain West over time Wednesday. Mid-level spin moves in Wednesday night starting at 06Z Thursday. This, coupled with low-level saturation will bring us cloud cover starting Wednesday night. At 03Z, mid-level southwesterly flow will begin at 06Z helping with the buildup of moisture. 

Thursday will bring us widespread rain over MO. The shortwave trough will eject out of the Mountain West and into Nebraska/Iowa at the mid levels. This will help aid in vorticity advection between Thursday 06Z and 21Z. Rising motion will help the development of precipitation starting near Thursday 12Z and continue until Thursday afternoon. The rain is expected to move out by Thursday evening as the surface low associated with the shortwave will move over Northern MO. A warm front attached to this low will slide through between Friday 00Z-06Z keeping clouds around Thursday night. NBM precipitation and KCOU plume analysis shows around 0.5 inches of rain between Wednesday night-Thursday.


-Simmons

 

 






Tuesday:
Cloudy with trace amounts of rain. High: 45



Tuesday Night:
Decreasing clouds. Low: 36




Wednesday:
Mostly sunny with increasing clouds. High: 53
 

 


Wednesday Night:
Increasing clouds and early-morning rain. Low: 42
 
 



Thursday:
Rain. High: 55

 

Thanks to IconArchive.com for the icons!


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

Discussion:

Be sure to pack an umbrella on Thursday as we are expecting around half of an inch of rain in the morning through the afternoon. Tuesday will also see some rain, but only trace amounts. Wednesday will be dry and mostly sunny, and high temperatures all week will be chilly but not too cold.

-Clark

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

Forecasters: Ritsema, Clark, Baker

Date Issued: 12/06/2022 9:00 AM CST

Technical Discussion: 
 

We chose to use the GFS for our forecast due to large variances between the NAM 00z and 06z runs, particularly with forecast precipitation accumulation. Both models were 3 or more degrees off of the high and low temperatures from the past 12 hours, which is likely due to leftover cloud cover from overnight Monday which kept our observed temperatures lower than numerical models forecast.

Tuesday we will see clouds build in from the west as increased values of 500 mb vorticity, 700 mb omega, and 700-850 mb saturation coincide. The saturation is broader and more complete in the lower levels however, so we will only see trace amounts of rain despite the associated areas of saturation and lift. Clouds will clear out by around Wednesday 09-12z. Overnight clouds will help to keep temperatures from reaching below freezing despite northerly winds. 

Wednesday will be mostly clear with clouds building in from the southwest as the day progresses due to sparse 700-850 mb saturation in mid-Missouri by Wednesday 21z which corresponds with small but noticeable amounts of 300 mb divergence, 500 mb vorticity, and 700 mb lift. While the areas of lift aren't broad and the values are low, they will be enough to encourage cloud formation Wednesday afternoon and evening. This won't result in precipitation, however, due to the shallow nature of the saturation; while RH values will be as high as 80%, they will be restricted to shallow layers near 700 mb and the overall area of saturation is small. 

Low-level clouds will have built in completely by Thursday 00z which corresponds with a wind shift at 850 mb from SW to S by 03z. This broad area of moisture, which corresponds with high amounts of 300 mb divergence; 500 mb vorticity; and 700 mb omega across southern and central MO, will result in moderate rain which will last from 03-06z to 21z Thursday. The rain is associated with a surface-based warm front, which is the result of a low pressure system which will be located over Wichita 18z Thursday and will continue to move into MO. We expect around a half of an inch from this rain system. 

-Clark

Monday, December 5, 2022

 





Monday Night:
Cloudy. Low: 38


Tuesday:
Cloudy with scattered showers. High: 44



Tuesday Night:
Showers. Low: 41
 

 

Wednesday:
Cloudy. High: 52
 
 


Wednesday Night:
Rain. Low: 49

 

Thanks to IconArchive.com for the icons!


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

Discussion:

We'll be seeing some rain this week. There will be two chances for rain, one on Tuesday into Tuesday night, and another during the overnight hours Wednesday into Thursday morning. When the sky isn't crying, clouds will still cover the sky until later this week.

-Cook

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

Forecasters: Herion, Cook, Kobielusz

Date Issued: 12/05/2022 5:00 PM CDT

Technical Discussion: 
 

Both the NAM12 and GFS had a good grasp on the location of a low pressure system over the panhandle of Oklahoma. However, the GFS had a better grasp of the surface temperatures.The NBM was also consulted for cloud cover and temperature prediction.

The sub-tropical jet continues to stay over the Midwest as a trough builds over Nevada. This trough looks to move through the Midwest late this week. There are strong divergence signatures Wednesday and into early Thursday morning.

Vorticity signatures follow suit with the divergence aloft. However, there seems to be a line of of vorticity that stays over mid-Missouri for much of Tuesday. Wednesday evening looks to be the highest chance of precipitation.

At 700 MB, RH signatures stay low until Tuesday afternoon. The GFS disagrees with the NAM over Vertical Velocity. The NAM shows stronger vertical velocity signatures while the GFS shows weak signatures. However, both agree with moisture at this level.

At the 850 level, a high pressure system stays over the Gulf of Mexico which will bring moisture to mid-Missouri. This moisture will stay through the forecast period.

Dewpoints at the surface will rise Wednesday due to the High pressure system over the Gulf of Mexico. RH levels show  A weak surface level low pressure system will move through Tuesday that could bring in scattered showers. Model sounding show saturation Tuesday evening into Wednesday morning. These look to be the best time for rain over our forecast period. GFS runs show trace amounts of rainfall Tuesday evening while runs show closer to half an inch Wednesday evening.

- Herion

 

 

 




Monday:
Cloudy with a high of 55 degrees Fahrenheit
 
 


Monday Night:
Cloudy with a low of 39 degrees Fahrenheit

Tuesday: Light Steady Rain with a high of 43 degrees Fahrenheit
 

 
Tuesday Night: Light Steady Rain with a low of 41 degrees Fahrenheit
 
 

Wednesday:
Cloudy with a high of 50 degrees Fahrenheit

 

Thanks to IconArchive.com for the icons!


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

Discussion:

Expect another week of cold weather as we begin December. Monday and Wednesday should be cloudy days, but be on the lookout for light steady rain Tuesday and into Tuesday night. Maybe bring with you your raincoat or umbrella to make sure you stay dry.

-Samson

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

Forecasters: Samson, Travis

Date Issued: 12/05/2022 9:00 AM CDT

Technical Discussion: 
 
Potential for rain on Tuesday and Tuesday night. For the forecasting period, both the GFS20 and NAM12 models were used, partiality was given to the NAM12, the reason why will be given further in the AFD.
 
Building on the aforementioned rain on Tuesday, a combination of rising air, low level saturation, and a warm front south of Columbia has lead to the possibility of light rain. Surface winds out from the northeast suggests the warm front's effect on the chances for rain. Emphasis for this forecast on light rain. The saturation is not deep enough to sustain moderate rainfall, petering out around 800 mb. So, if we do get rain it will be minimal. For the most part outside of Tuesday there is not a lot of noteworthy things happening in the atmosphere. At the end of the period, at the 250- and 300-mb level, on Wednesday there is a jet core moving through Central Iowa into Illinois and Wisconsin that is causing some divergence over the forecasting area at 18z. However, it does not last very long. The GFS predicts a lot more divergence than the NAM, but there does not seem to be reason for that. So, the NAM's prediction seems more reliable.

Future forecasters should be aware of an approaching center of low pressure that is moving northwest. Currently and through the period it has not seemed to have affected the Columbia area yet. However, as it approaches it will bring with it significant low-level convergence, positive vorticity, and negative omega. Impacts on future weather predictions will be seen in the coming days.

-Samson