Friday, March 26, 2021

Current Conditions at Sanborn Field

 


Friday Night -
Partly cloudy. Low: 46-50
 
 


Saturday -
Increasing clouds showers and storms after noon. High: 70-74
 
 


Saturday Night -
Rain ending by late evening. Low: 38-42

 



Sunday -
Mostly sunny and colder. High: 54-58
 
 
 

Monday -
Mostly sunny. High: 62-66

================================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 

As surface high pressure scoots off to the east of Missouri, it will set up dominant southerly flow that will help keep temperatures on a warming trend through Saturday. As a low pressure system to the north approaches the Midwest, an associated cold front will bring with it showers and thunderstorms Saturday afternoon. Stay weather aware as some storms may be on the stronger side. The bulk of the severe threat should stay to the southeast of the region. The cold front will pass through Columbia by sunset on Saturday after which thunderstorms will be pushed out of the area while trailing showers will linger into late Saturday night into very early Sunday morning. Skies will clear up as and temperatures will be substantially cooler Sunday behind the front.


*** The Mizzou Campus Weather Forecast will be on spring break next week and will return on Monday April 5th at 10am***

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

 
Forecaster: Bongard, Travis
Issued: 5PM CDT 26 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):

 

For the Friday afternoon forecast a blend of the NAM and GFS was used for this forecast period. NAM was dealing with the placement of low pressure to the west a bit better than GFS. GFS on the other hand was running much closer to reality in terms of current temperatures in which NAM was 10 degrees warmer than observed. Both SREF and GEFS plumes were also analyzed to determine model efficiency through the weekend. Model soundings were heavily utilized to deal with the main issue of this forecast period which was probability and potential timing of convective development over the weekend. 

 

250-mb NAM model analysis is featuring a broad yet well amplified trough over the western two-thirds of the CONUS with its axis draped from central Canada down into the Rockies where its base just off the southern California coast. This promotes west-southwest flow over mid-Missouri today and this evening. Over the course of tonight and tomorrow this upper level trough will swing its base across the desert southwest. The jet embedded in its upstream flow will promote divergence aloft tomorrow afternoon and evening which should be kept in mind for convective potential Saturday. The axis of the trough will push through the central CONUS Sunday and open the Midwest up to upper level ridging by the end of the forecast period Monday afternoon.

 

500-mb analysis reveals bountiful vorticity values embedded in the base of the trough just off the west coast. Over the course of the evening and tonight said vorticity along with energy being advected into the region from the northwest thanks to a deepening trough over northern Plains will merge over the Midwest and provide the catalyst needed for convective activity tomorrow afternoon. These high values of vorticity will advect to the east away from central Missouri by 15Z Sunday morning as the ridge to the west begins its influence on the area. A lack of vorticity exists for the rest of the forecast period.


Low level model analyses suggests a tale of two advections. WAA will dominate the early portions of the period lending to the warm temperatures this afternoon and moreso Saturday ahead of the encroaching cold front. Frontal passage looks to occur by 23Z tomorrow evening and the transition to a CAA regime will begin. A post frontal regime will build into Missouri from the northwest with northwesterly flow advecting those colder temperatures over the state promoting colder temperatures Sunday. Convergence at 700 mb Saturday afternoon lends confidence to the chances for convective development at that time.


Model sounding analysis was critical in determining timing and convective potential tomorrow afternoon. The profile moistens up significantly after 18Z Saturday as PWAT values climb rapidly to around 1.10 inches by 21Z. While the majority of that moisture exists near the 850-mb level Omega values at that layer support sufficient lift to move that moisture to a necessary height for convective development. CAPE values are ample topping out between 1500-2000 J/kg tomorrow afternoon with the slight capping inversion breaking shortly after 18Z. These CAPE values will maintain through early evening when the wind profile suggests front passage at roughly 22-23Z. Total totals in the 60 and K-index values in the mid 30's at these times suggest brief heavy convective rain. This all adds up to perhaps a strong line of showers and thunderstorms developing over central Missouri tomorrow afternoon before racing to the east-southeast where even strong convective environments exist. PWAT values will persist into the late evening promote a chance for some post-frontal precipitation. Accumulations all depend on exactly where in central Missouri that convective line develops. If the line forms to the north-northwest Columbia could see as much as 0.25 inches as the line pushes through. Otherwise Columbia could see as little as a trace of rain from this system.

 


Thursday, March 25, 2021

 

Current Conditions at Sanborn Field

 

Thursday Night -
Rain stopping around 10pm staying mostly cloudy. Low: 36-40
 
 

Friday -
Mostly cloudy becoming overcast. High: 58-62
 
 


Friday Night -
Overcast with light showers. Low: 48-52

 
 


Saturday -
Isolated showers beginning in the evening. High: 70-74
 
 
 

Sunday -
Mostly clear. High: 56-60

================================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 

    Rain will continue throughout the evening on Thursday with the exodus of the low pressure system currently over the area. Lingering moisture in the area will result in widespread cloud cover over the area for most of the day on Friday. Strong southerly flow of winds will contribute to the rising temperatures we will experience on Saturday. Due to a cold front passage on Saturday night, temperatures will start to decrease as well as increased chances for light rain scattered over Missouri. The moisture and rising air associated with the cold front will further help the chances for isolated showers and storms on Saturday evening into Sunday. Finally on Sunday, due to the cold frontal passage mentioned above, the direction of wind will switch back to northerly early Sunday morning along with a much drier atmosphere resulting in a more cool and calm end to the weekend.  


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

 
Forecaster: Lamb, Nixon, Cochran, Travis
Issued: 6PM CDT 25 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):

 

    The GFS was used in this forecast because it produced sea level pressures and temperatures closer to the observed analysis. The focus of this forecast is the longwave trough moving east across Central Missouri and the WAA causing unseasonably warm temperatures on Saturday.

    According to the GFS, in the upper atmosphere, there is a jet streak identified at the 250-mb level over Missouri, oriented southwest to northeast. This helped give rise to the storm system that dominated the area on Thursday. By late Thursday night, a shortwave trough from the western United States will push the remaining divergence out of Missouri, forcing the rain out along with it. This shortwave is followed by a more significant long-wave trough that is going to have the most significant impact on the forecast area.

    Into the 500-mb level, the short-wave trough is still present, but moves northeast out of the region. The long-wave trough follows in its wake, creating a strong southwesterly flow aloft. Around 00Z Saturday, another short-wave trough passes over Central Missouri. Circulations that accompany this trough, will support rain showers into Friday night. However, due to little moisture in the atmosphere, severe weather will not be likely. As the trough axis approaches from the southwest, strong circulations and upward motion enter the area on Saturday evening. This increases the likelihood of isolated showers and thunderstorms. Sunday experiences pleasant conditions as northwest zonal flow dominates the area.

    At 700 mb, there is still a dominant southwesterly flow. Relative humidity plots at this level shows most of the moisture leaving the area Thursday night, as the low-pressure system moves northeast. After the low passes, Central Missouri stays relatively dry until the trough axis travels over the area on Saturday evening. This will give a chance for some precipitation and isolated storms.

    At the surface, the low-pressure system continues to move to the Northeast leaving a strong southwesterly flow. In combination with the solenoids seen at the 500-1000-mb thickness and
MSLP plot, strong WAA is expected to bring unseasonably warm temperatures on Saturday. A surface low starts to develop to the west of Missouri early Saturday and pushes northeast. Branching off from this low, is cold front that will move through Columbia on Saturday evening. Isolated showers and thunderstorms are possible for the region as the cold front pushes east. Sunday is expected to be cooler after the passage of the cold front, as the winds turn northwesterly initiating CAA.

    The future forecast period should focus on the zonal flow that dominates the Midwest.


 

Current Conditions at Sanborn Field



Thursday -
Rain, especially in the afternoon. Breezy. High: 48-52.
 
 

Thursday Night -
Mostly cloudy. Rain moving out in the evening. Low: 38-42.
 
 

Friday -
Partly sunny. High: 60-64.
 
 

Friday Night -
Gradually clearing by midnight. Low: 48-52

 
 

Saturday -
Sunny with lingering clouds. High: 66-70. 

================================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 


Today temperatures are going to have a hard time increasing as there is a low pressure system that will push through the area bringing rain along with it. At times this precipitation could be heavier, but overall there is no potential for severe weather. Precipitation totals will fall between 0.5-1.0 inch of rain. This precipitation will begin to move out into the overnight hours. Humidity will stick around in the morning hours on Friday, but then will begin to clear. Mid-Missouri will start to fall into a warming trend between Friday and Saturday before our next cold front begins to move in Saturday night.

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

 
Forecaster: Ede, Gasch, Pauley
Issued: 10:00 AM CDT 25 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):

 

The GFS was used in this forecast as the NAM was forecasting much cooler temperatures than the GFS and the GFS was forecasting sea level pressures closer to the analysis. The focus of this forecast is the system moving through today and very warm temperatures for Saturday.


Starting in the upper atmosphere at 250 mb, there is a jet streak over Missouri, oriented southwest to northeast. This upper level flow is what will guide the storm system today and into the weekend. Additionally, the upper level divergence situated over Missouri will increase the possibility of moderate rain today. By 00z tonight, a shortwave trough will push the last of the divergence out of Missouri, forcing the rain along with it. This shortwave is followed by a more significant longwave trough that is going to provide strong southwesterly upper level flow for Friday and Saturday.


Moving down to 500 mb, there continues to be southwesterly flow over Missouri. The low at 500 mb is over Southeast Missouri, showing a slight negative tilt to the system, indicating a potential for strengthening in the next 12-24 hours. This strengthening will not affect Missouri, though. Strong circulations associated with this system will pass through Missouri, providing increasing likelihoods of rain. By Saturday, Missouri is under a strong southwesterly flow regime. A strong upper level trough will also develop by Saturday, driving the next big weather change.


At 700 mb, there is still southwesterly flow. The upper level low becomes slightly stacked underneath the 500 mb low, so the low may not develop as much. Associated with this low is a lot of moisture and strong vertical motion, which will influence the rain for today. After the low passes, the moisture continues to stick around as the influence from the upper level trough increases in the Missouri area. However, this moisture will not bring anything more than a scattered cloud. 


Down at the surface, Missouri is under the influence of cold air advection for today, but that will switch to warm air advection by Friday night and Saturday, driving increased temperatures for Saturday. For today, rain is going to start between 15Z and 18Z and will likely end between 03Z and 06Z. Missouri will see between 0.5 inches and 1 inch of rain throughout Friday.

 

Looking ahead, Saturday will be unseasonably warm. By Saturday evening, the potential for strong storms will coincide with a cold front that will pass through Missouri Saturday evening. Saturday night will need to be focused on for future forecasters.

Wednesday, March 24, 2021

Current Conditions at Sanborn Field


Wednesday Night - 
Cloudy. Slight chance of rain late. Low: 42-46.



Thursday -
Rain, especially in the afternoon. Breezy. High: 48-52.


 
Thursday Night - Mostly cloudy. Rain moving out in the evening. Low: 38-42.



Friday -
Partly sunny. High: 60-64.
 
 

Saturday -
Partly sunny. High: 66-70. 

================================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 

After a dry Wednesday and Wednesday night, rain will re-enter the forecast starting Thursday morning. A low pressure system will slide by to our south Thursday afternoon, giving mid-MO a very good chance of widespread soaking rain starting mid to late morning Thursday. Breezy conditions are also possible as the rain moves through. Rain and clouds will keep highs on Thursday down in the upper 40s to lower 50s. Rain will move out Thursday evening, leaving us dry for Friday. Clouds will still hang around for Friday and Saturday, however, and there's an outside chance of a few light rain showers Friday evening. The good news? Temperatures will trend warmer as we head into the weekend, with readings near 70 possible by Saturday.


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

 
Forecaster: Vanderpool
Issued: 5:00 PM CDT 24 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):

After a brief reprieve from the wet weather on Wednesday, another round of widespread rain is expected in mid-MO late tonight into Thursday. 


WPC surface analysis places an occluded surface low over the upper Midwest. This system was responsible for the wet weather in mid-MO on Tuesday. As this low pushes northeast, another sfc low is projected to develop and undergo rapid cyclogenesis across the lower Midwest through Thursday afternoon. The GFS and NAM both concur in placing mid-MO in an ideal place for the strengthening of a surface low, with ample divergence at 250-mb by 18 UTC Thursday courtesy of coupled jet streaks. 


Overnight, skies will remain overcast ahead of the developing surface cyclone. GEFS and SREF means, along with the 18 UTC HRRR, have lows only falling into the middle 40s. Moist flow should begin to establish itself in the lower levels of the atmosphere by daybreak Thursday, though significant lift will not arrive until the developing closed low slides into Missouri around the late morning to early afternoon hours. 


For Thursday, rain looks to start in earnest around or shortly after 15 UTC (10 AM CDT). The shortwave aloft will support a deepening closed circulation at the surface by midday, with the track of the surface low likely falling around 100 miles southeast of Columbia. This will support a small deformation zone on the backside of the cyclone, placing COU in an ideal location to receive some fairly significant rainfall amounts despite a lack of instability. The deterministic GFS, NAM, HRRR, and the GEFS all support a period of moderate to occasionally-heavy rain Thursday afternoon, with the heaviest precipitation likely to occur between 12 PM and 8 PM CDT. The HRRR and SREF means both peg QPF around 0.5", whereas the GFS, GEFS, and NAM are significantly more bullish, showing around an inch. Given the rapidly-deepening nature of the storm system and PWATs near 1 inch, it's likely that Columbia sees anywere from 0.5 - 1 inch of rain out of this system. Additionally, the pressure gradient on the backside of the surface low will intensify Thursday afternoon, so breezy conditions are likely along with this rain. 


Precipitation looks to clear out Thursday evening. Clouds should hang around through at least the first half of the night before breaks of clear sky are possible towards Friday morning. Given modest CAA and the potential for some clearing, lows Thursday night should be rather chilly: near 40 degrees. 

 

Sensible weather looks to be quieter on Friday, though the longwave trough will still be to our west. That will encourage the development of yet another surface low on the lee side of the Rockies, which could spread more cloud cover over mid-MO during the day on Friday. Nevertheless, I think the majority of the cloudiness will pass just north of Columbia. That, along with modest WAA, will lead to highs in the lower to middle 60s. 

 

Saturday looks similar, though the aforementioned surface low will be skirting by just to the north. It appears moisture-starved at this time but ensemble models do indicate low POPs Friday night into Saturday. Interested parties should monitor the forecast for a rain potential during that time. Additionally, despite decent WAA ahead of an associated cold front on Saturday, cloud cover (or lack thereof) in association with the low will determine whether or not highs will break 70 degrees. Right now, cloud cover and the timing of the front seem to advocate for highs in the middle 60s to near 70. If the forecast trends sunnier, these highs may need to be raised.

 


   Wednesday -
Overcast. High: 54-58



 
Wednesday Night - Overcast. Rain possible after midnight. Low: 42-46


 
Thursday- Cloudy. On and off rain showers and thunderstorms. High: 52-56



Thursday Night-
Clouds begin to thin. Rain clears out. Low: 38-42
 
 

Friday -
Partly sunny. High: 60-64 

==================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 
We're waking up to a gloomy morning, but things will stay dry throughout the day. You may want a jacket with temperatures being slightly cooler, but you can hold off on the umbrella until tonight. Rain chances will enter the area after midnight and be with us through most of the day on Thursday. We could hear a few rumbles of thunder mix in with the rain showers Thursday afternoon, but we're not concerned with any severe weather in the area. Winds will shift throughout the day Thursday to become northwesterly. This, combined with clearing clouds overnight Thursday will allow for low temperatures to fall much lower than we've been seeing. Friday morning, as low pressure pushes off to our east, we'll wake up to some sunshine mixing in with leftover clouds. Overall, Friday will begin a drier pattern as we head toward the weekend.

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

 
Forecaster: Baker and Est
Issued: 10:00 AM CST 24 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):


This forecast was assembled using the 06Z run of the GFS with aid of GFS soundings to determine storm potential and rain likelihood. The GFS was chosen due to how well it has handled both initial conditions and the timing and intensity of incoming rain events. 

 

The 250-mb plot winds shows a jet max to our southeast throughout the day on Wednesday. By 09Z Thursday, a jet max begins to move through Missouri until 09Z Friday. Friday shows no significant jet max near the forecast area.

 

500-mb vorticity outputs for Wednesday are lackluster, but we begin to see vorticity enter the region overnight Wednesday into Thursday around 06Z Thursday. Vorticity increases throughout the day Thursday with the highest amounts of vorticity being located over the forecast area at 21Z Thursday. As vorticity increases, this will aid in the possibility for thunderstorm development for the afternoon Thursday. Vorticity decreases throughout Thursday evening, and there is no expected vorticity to impact the area for Friday at this level.

 

The 700-mb plot shows a lack of RH until 06Z Thursday where RH levels increase dramatically. High RH levels will stick with us until 09Z Friday when things become drier. Having moisture at this level coupled with lower level saturation seen on soundings suggests a rain event throughout Thursday. Winds at this level are westerly throughout Wednesday, but at 06Z Thursday, as the low passes by Missouri, winds will shift to become more southerly. This will allow for moisture transport from the Gulf of Mexico, ultimately increasing rain chances for Thursday.

 

At the 850-mb level, the low pressure system that impacted our weather yesterday continues to push off to the northeast. Winds at this level start out as westerly Wednesday, but they are expected to shift to become southerly at 06Z Thursday. Southerly winds will be with us throughout the day Thursday, but they will shift to become westerly again by 03Z Friday.

 

The surface level shows several differences between each day of the forecast period. As the surface low pressure system in the southwestern portion of Texas continues sliding northeast, it will cause wind direction changes as it passes through the Missouri boot heel. Wednesday, winds will be WSW at 10mph, but they will become northerly for Thursday. This will allow temperatures to remain cool at the surface for Thursday. Friday, we will continue to see winds out of the north, but sunshine should aid in warming temperatures. 


All guidance for the forecast period suggests a rain event from 06Z Thursday through 00Z Friday. We could see a brief break in the rain from 09Z Thursday until 15Z, but the second round of rain could have some thunder embedding within it. Soundings for this time period suggest CAPE values increasing for the afternoon Thursday, but with mostly positive Omega values, hail is not a concern. In total, we could see near 1.0" of accumulating rainfall by Friday morning.


Future forecasters should watch the storm potential for Thursday afternoon.

Tuesday, March 23, 2021


Current Conditions at Sanborn Field


Tuesday Night - 
Cloudy. Rain ending in the early evening. Low: 44-48



Wednesday -
Cloudy and breezy. High: 54-58 



Wednesday Night - 
Cloudy. Rain possible after midnight. Low: 44-48



Thursday -
Cloudy. On-and-off showers possible throughout the day. High: 52-56
 
 

Friday -
Partly sunny. High: 60-64 

==================================================== 
 Thanks to IconArchive.com for the icons!

Discussion: 

This evening you may run into some rain on your way home from work, but thankfully these showers are expected to end by the early evening. Wednesday will stay dry, but cloudy skies will stay with us on-and-off throughout the remainder of the week and daytime temperatures will remain in the comfortable 50s to low 60s. Wednesday night, our chances for rain will return, and stay with us throughout the day on Thursday. If you are planning on going out, make sure to bring your umbrella and maybe even some rain boots. Finally, the clouds will begin to clear out a bit on Friday and the sun will return to warm up our temperatures into the low 60s.


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

 
Forecaster: Clemons, Orr, Vochatzer
Issued: 5:00 PM CST 23 March 2021
 
Technical Discussion (The nerdy stuff we are discussing in class):


This forecast was assembled using the 12Z run of the GFS, SREF and GEFS plumes for temperatures, and GFS soundings for rain potential and timing. The GFS was chosen due to how well it has handled both initial conditions and the timing and intensity of incoming rain events. 

 

The 250-mb plot of heights, winds and divergence shows the large amount of divergence passing over Mid-Missouri due to the occluded low pressure system over central Kansas. By Wednesday, the low will have moved out of the region to the northeast, and Missouri falls under the influence of a large jet streak. Thursday sees more large amounts of divergence, which will help fuel the next opportunity for rain in central Missouri. This jet streak influence remains until the end of the forecast period. 

 

500-mb plots of heights and vorticity depict the occluded low as it moves over northern Missouri. As it passes, it brings the potential for severe storms for the northeastern portion of Missouri. After the low passes, enough vorticity is left to retain cloudy conditions, but a lack of moisture in lower levels should prevent rain from occurring. By 06Z Thursday, the passage of a shortwave trough brings more potential for rain, and the potential stays there for the remainder of the day. As of 09Z Friday, Missouri falls under the influence of a shortwave ridge, bringing calmer conditions and a break from the on and off rain pattern. 

 

The 700-mb plot of heights and relative humidity explain why Missouri will see so many fluctuations in opportunities for rain. The occluded low takes the classic comma cloud shape, which brings enough moisture for central Missouri to receive rain until the early evening around 00Z Wednesday. Enough available moisture for rain stays out of the area until 06Z Thursday, where moisture will fluctuate throughout the day, causing spotty on and off showers. By Friday, all abundant moisture leave Missouri and calm conditions return. Future forecasters should be aware that more moisture will be moving into the region Friday night, bringing more potential for rain. 

 

At the 850-mb level, plots of heights, winds and temperature depict just why Missouri will see so many moisture fluctuations. The LLJ from the Gulf of Mexico funnels in moisture for Tuesday evening's rain event. The passage of the low cuts off the LLJ around 00Z Wednesday, preventing anymore rain chances for the day. After the low passes, the LLJ returns at 06Z Thursday, funneling in more moisture and causing rainfall to return to central Missouri. By 00Z Friday, winds change to a westerly direction and bring clearer skies and calmer conditions. 

 

Surface plots of MSLP, thickness and winds suggest that another low pressure system will be the cause for Thursday's rain chances. After the passage of this system, calmer conditions return, as suggested by very widely spaced isobars. By Friday afternoon, WAA takes over, suggesting warmer temperatures than previously seen throughout the week.