Monday, March 18, 2019

Monday - Mostly clear skies becoming partly cloudy in the afternoon. High: 50-54

Monday Night - Skies becoming cloudy. Low: 32-36

Tuesday - Cloudy skies. A stray afternoon shower is possible. High: 52-56

Tuesday Night - Cloudy skies with rain, especially after midnight. Breezy. Low: 42-46

Wednesday - Cloudy skies remain. Drizzle persisting into morning, ending before noon. High: 50-54

Thanks to for the icons!


Enjoy the remainder of the sunny skies that mid-Missouri saw this past weekend, because they will not be sticking around. Clouds will move in Monday night and will stick around for the remainder of our forecast period. Highs will remain seasonal in the mid 50s. We've entered a very early springlike pattern of rollercoaster temperatures, so dress warm in the morning, but shed those layers by the afternoon. Tuesday looks to be our warmest day with Highs potentially reaching 56 degrees. Tuesday night rain is likely beginning after midnight, but diminishing before sunrise with the potential for drizzles into the Wednesday morning commute.

Forecasters: Ritter and Travis
Issued: 10:00 a.m.March 18, 2019

Technical Discussion (The nerdy stuff we are discussing in class!)

Pleasant weather from this weekend will persist through the day today. Columbia continues to reside in an area of high pressure centered over Nebraska, which is causing such pleasant weather. This high pressure center will drift southeast through northern Missouri throughout the day today, keeping our weather calm. As we move through the day today, however, Columbia will begin to feel the effects of Tuesday Night's system. GFS Skew-Ts show moistening in the column between 250 and 400 hPa. While this layer does not look to be completely saturated, there does look to be enough moisture present to produce some high clouds during the afternoon. Moving into tonight, GFS Skew-Ts show the moist layer in the column deepening down to 700 hPa with complete saturation between 250 and 300 hPa and between 500 and 550 hPa by 12Z Tuesday; therefore, Columbia should have completely overcast skies by this time. Progressing through the day Tuesday, cloudy skies will persist. There may also be a stray shower or two during the afternoon and evening Tuesday, although GFS Skew-Ts show a thick dry layer between 850 hPa and the surface, and there will be very little lift in column during this period.

The main story of this forecast has to do with Tuesday Night's system. Between 00Z and 12Z Wednesday, the GFS advertises a 110-kt 250 hPa jet core will move through the Southern Plains and into the Lower Mississippi Valley, putting Columbia close to the left exit region of the jet streak. As would be expected, several areas of divergence will pass over mid-Missouri during this period. A positively-tilted 500 hPa shortwave trough and associated vort max will also be dropping south toward Missouri from the Northern Plains. As this shortwave progresses toward Columbia, moisture and lift will be maximized at 700 hPa, especially between 06Z and 12Z. A 40-kt LLJ at 850 hPa will also aid in moisture transport between 00Z and 12Z Wednesday. The only question with this system is moisture at the surface. GFS Skew-Ts show a dry layer between 850 hPa and the surface through 06Z Wednesday, with the 09Z Wednesday Skew-T showing saturation through to the surface. With this being said, we cannot rule out a stray rain shower or two as early as 21Z Tuesday, so we have mentioned at least a possibility of rain beginning Tuesday afternoon, becoming likely after 06Z Wednesday when the column moistens all the way to the surface. Precipitation amounts from this system will not be very large, as the SREF QPF ensemble mean is around 0.25" and the operational GFS goes with around 0.20".

By 12Z Wednesday, GFS Skew-Ts show no lift in the column, and a large dry layer begins to develop between 500 and 850 hPa, but a moist layer remains between 850 hPa and the surface. This moist layer will persist through about 18Z, even as the column above it dries out. Finally, by 21Z, the moist layer between 850 hPa and the surface will begin to dry out, starting at the surface, and by 00Z Thursday, the layer should be dry. With this said, our forecast calls for low clouds and possible drizzle before 18Z Wednesday, with low clouds beginning to break up by 00Z Thursday.

As for temperatures, highs throughout the period should be roughly similar each day, with highs in the 50s. If anything, Tuesday would be the warmest day of the period due to WAA during the afternoon, as evidenced by a veering wind profile with height in GFS Skew-Ts. Lows overnight tonight will be in the 30s, but lows overnight Tuesday into Wednesday should be in the 40s due to the aforementioned WAA.

No comments:

Post a Comment