Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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028 FXUS63 KARX 051926 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 226 PM CDT Sun May 5 2024 .KEY MESSAGES... - Periods of showers from Tuesday through Friday. Best chance for rain at this point is early Tuesday morning and again Wednesday through Thursday. - Cooler air settles in after midweek, but overall look for seasonal temperatures into next weekend. && .DISCUSSION... Issued at 227 PM CDT Sun May 5 2024 Active Weather Pattern Next Week: Shortwave ridging will be over the area through Monday. As this ridging comes to an end, an area of low pressure will move through the Plains and into the Upper Midwest. Convection will increase in coverage in the Plains during the day on Monday. Eventually a line of showers and thunderstorms will form by Monday evening across the Central Plains. This line is expected to move through the area during the overnight hours between Monday night and Tuesday morning. When the line moves across the region, instability will be pretty limited, as a couple hundred joules of CAPE is all there will be. The trough bringing the low into the region will also become negatively tilted as the precipitation moves into the area and will eventually become an elongated low providing us with zonal flow. With these things considered, as well as the timing of when these storms arrive, no severe weather will be associated with this line. All of the severe weather will be to our southeast into the Ohio River Valley. The previously mentioned elongated low is expected to stick around through Thursday and in doing so, a couple shortwaves will shoot off from this low and provide the area with some more rain chances. The first opportunity is Tuesday afternoon and into the evening. Then a small break in rain chances from Tuesday night into Wednesday morning as shortwave ridging builds in ahead of a strengthening shortwave that will move through Wednesday into Thursday. Model guidance shows this shortwave stalling over our area for a little bit as the parent elongated low shifts westward and a shortwave trough moves down from the north. By Thursday, this shortwave will absorb into the shortwave trough and move out Thursday afternoon. Given that these smaller scale synoptic patterns can change, confidence is not high in how the shortwaves and shortwave trough will interact. There is good agreement however, that this pattern will give the area periodic chances of showers and thunderstorms through the weekend. With this northerly flow pattern, cooler air will move through and thus temperatures are expected to drop into the upper 50s to mid 60s from Thursday through Saturday. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1115 AM CDT Sun May 5 2024 CIGS: SKC conditions for the most part through Monday morning. Clouds will then be on the increase for Monday afternoon/night ahead of the next upper level shortwave, likely dropping into MVFR overnight. WX/vsby: not anticipating any fog concerns (valley in specific) tonight. Rain returns overnight Mon, with some embedded thunder possible. Likely drop into MVFR vsbys with the rain. WINDS: light and mostly variable into this evening, picking up from the southeast overnight/Mon morning. Could see some afternoon/eve gusts Mon into the lower 20 kts. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Cecava AVIATION...Rieck