Monday Night: Chance for t-storms. Low: 60°F
Tuesday: Cloudy. High: 66°F
Tuesday Night: Clouds clearing. Low: 42°F
Wednesday: Sunny. High: 62°F
Wednesday Night: Partly cloudy. Low: 42°F
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General Discussion:
Following the off and on rain we’ve seen all day today, we will have a final band of showers and t-storms move through this evening and overnight. These storms have the potential to be strong to severe (damaging winds and isolated tornadoes) though no widespread severe weather is expected. After this we can expect a return to seasonable temperatures (60s) through the midweek.
– Aldrich, Bean, Carrier
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Forecasters: Aldrich, Bean, Carrier
Date Issued: 11/04/2024 5:00 PM CST
Technical Discussion:
Key Messages
-Thunderstorms to come tonight with the most likely threats being strong winds, and a few isolated tornadoes.
-Seasonal temperatures return after a cold front moves through on Tuesday.
The main driver of the dreary weather we’ve been having lately is the leading edge of a slightly positively tilted trough, centered over the western plains that has been pulling moisture up from the Gulf of Mexico and creating areas of strong upper level divergence. This upper level divergence corresponds to areas of convergence at the surface which is promoting the development of more convective systems out of the off and on rain we have been seeing all day. As we move into the evening and overnight we should expect the rainfall to intensify as the saturated layer deepens to connect thinner low level and high cloud layers producing an almost completely saturated profile. This deepening moist layer has significant vertical velocity associated with it and increases our chances of having some storms increase in severity. While the instability factors for our area are not favorable for large-scale severe storm development, a strong low level jet stream, along with surface-6km wind shear will have the potential to kickstart some severe t-storms and isolated tornadoes. The Storm Prediction Center has Columbia under a slight (⅖) risk for severe thunderstorms.
Moving into the rest of the week, the trough that is currently over the western plains will deamplify out of existence Tuesday morning as a low from Canada moves down over the Rockies and forms a significantly positively tilted trough with its axis extending from Arizona To Minnesota. This trough has a widespread area of associated vorticity at 500mb covering a large portion of the central and western CONUS. This vorticity will likely not contribute to any active weather however as the atmospheric profile remains mostly dry after the clouds clear out on Tuesday with only a few low clouds possible by Wednesday. The 700mb layer dries out on Tuesday as the shift in the upper level flow cuts off the moisture from the Gulf and replaces it with dry air from the desert southwest and prevents the moisture at the center of the low from expanding eastward. With this change, our local weather will shift to seasonal temperatures (60s) and calm weather through the midweek.
-Aldrich, Bean, Carrier