Monday, April 22nd – Afternoon Forecast
Monday Night: Partly Cloudy. Low: 50°F
Tuesday: 30-40% Chance of Light Rain In Morning. High: 66°F
Tuesday Night: Increasing Clouds. Low: 43°F
Wednesday: Decreasing Clouds. High: 68°F
Wednesday Night: Mostly Cloudy. Low: 48°F
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General Discussion:
After a quiet night tonight, a brief chance (30-40%) of light rainfall in the morning and early morning hours is expected tomorrow. More quiet weather returns on Wednesday before a more active pattern becomes present at the end of the week.
-Jackson
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Forecasters: Jackson, Beam, Sallot
Date Issued: 04/22/2024 5:00 PM CDT
Technical Discussion:
Both the NAM and the GFS models were used for this forecast period. Both are in agreement with the latest runs, leading to higher confidence in messaging.
Key Messages:
- Upper-level moisture gradually returns through the overnight hours, but overall settled weather is expected tonight.
- A brief chance (30-40%) of light showers is expected Tuesday morning 15-18z as components are lacking for a more impactful system.
- An upper-level ridge brings quiet weather throughout the rest of the forecast period, although more upper-level moisture is expected to present persistent clouds.
A low-pressure system over North Dakota and portions of Canada will be the focus of this forecast period. As it propagates to the southeast later tonight, upper-level moisture will become apparent in northeast Missouri, although more widespread moisture over central Missouri will be present by 06-09z Tuesday. This is why a partly cloudy sky is anticipated tonight with temperatures falling into the low 50s due to radiational cooling.
Tuesday morning (15-18z) is the best chance at observing any rainfall, but the expected accumulation is little to none. No organized convection is expected either as model soundings show a strong inversion present throughout the passage of this chance of rainfall, leading to no CAPE for storms to be fueled by. Vorticity is also a factor in hindering organized convection as there is little to come by in Missouri. As upper-level moisture traverses into the area 15-18z Tuesday, ascent along upper-level moisture will be hard to come by (-3 to –7 µbar/s). This is why at most, light rainfall can be expected throughout the mentioned time period. By 21z Tuesday, upper-level moisture will be in southeast Missouri, creating a clearing in central Missouri. This will allow for a window of daytime heating, but high temperatures will be hindered by the chance of morning rain and cloud cover. This is why the expected high for tomorrow is in the mid 60s.
Zonal flow is expected after 21z Tuesday into Wednesday which will usher out moisture that is present over Missouri. This will lead to a clearing by Wednesday and allow for plenty of daytime heating. This is why high temperatures on Wednesday will be in the high 60s by 21z. An approaching ridge will also assist in the warmup process as it provides sinking air, further warming central Missouri up. Wednesday night into Thursday morning, the ridge axis will pass through the area, leading to southerly flow by 12z Thursday. This southerly flow will advect moisture into southwest Missouri, leading to increasing cloud cover.
Future forecasting shifts should be aware of the active end to the week as there are multiple systems bringing strong storm opportunities. The first opportunity will be after the passage of the ridge axis.
-Jackson