Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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073 FXUS63 KARX 231113 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 613 AM CDT Sun Jun 23 2024 .KEY MESSAGES... - Showers and thunderstorms return to the forecast Monday night and Tuesday, with a conditional risk for severe thunderstorms. A Slight Risk (level 2 of 5) for severe weather remains for Monday night and for a small portion of our southern counties on Tuesday. - Another brief break for mid-week before additional shower and storm chances return late in the period. Details to be refined in the coming days. && .DISCUSSION... Issued at 349 AM CDT Sun Jun 23 2024 Today - Monday: After a very active couple of days, it looks like we are finally getting a much quieter end to the weekend. Current satellite water vapor imagery and RAP progs show a shortwave dropping down from Canada towards northern Minnesota. This wave is forecast to continue down and eventually across the Great Lakes through the day. This along with daytime heating may allow for some isolated showers (perhaps a storm) to develop this afternoon, especially to the north. Otherwise, expecting a much drier day for most with highs mainly in the 70s to low 80s for a few. Surface high pressure slides across the region Sunday night with drier conditions and increasing temperatures (80s) into Monday. Take advantage of the next couple of days as showers and thunderstorm chances make a return to the forecast. Monday Night - Tuesday: An upper level shortwave trough and attendant surface low are forecast to move eastward across portions of Canada Monday into Tuesday. The aforementioned surface high pressure passes through on Monday and southerly flow sets in, with increasing moisture and warm advection across the area. With this and an increasing low level jet Monday night, model guidance suggests the potential for showers and storms to develop. Given the thermodynamic environment guidance shows quite strong instability building in, which would generally be supportive of strong to severe storms. However, there still remains quite a bit of uncertainty revolving around storm coverage and evolution, with model forecast soundings showing a stout cap in place. With this the risk for severe weather remains a challenge and likely conditional with some details still unclear. For now, SPC has maintained a Slight Risk (level 2 of 5) for severe weather across northern portions of the forecast area. As the shortwave trough continues to track across Canada Tuesday, an associated cold front is forecast to move across the region. This may become a focus for further showers and thunderstorms to develop Tuesday. However, how this all evolves will likely depend greatly on how the Monday night storms evolve. At this time much of the area remains in a Marginal Risk (1 of 5) for severe weather, with a small portion of northeastern Iowa and southwestern Wisconsin counties just within a Slight Risk (2 of 5) for Tuesday. Mid-week onward: Behind the early week systems, a bit cooler temperatures (70s to around 80) and another much needed break in showers and thunderstorms looks to come for mid-week. However, another system is forecast to track across the northern Plains bringing this break to an end. Plenty of variability among ensemble solutions still exists this far out, so stay tuned as we refine the details over the coming days. && .AVIATION /12Z TAFS THROUGH 12Z MONDAY/... Issued at 613 AM CDT Sun Jun 23 2024 IFR/MVFR stratus continues to move down across the forecast area this morning. As we head through the morning expecting there should be some improvement to VFR, with SCT-BKN diurnal cumulus developing for this afternoon. Northwest winds remain through the day with some occasional increased wind gust possible. Otherwise, light and variable winds overnight turn more south/southeast for Monday. A few isolated showers may develop this afternoon, but with low confidence in any impacts to the TAF sites have not included any mention at this time. Otherwise, some model guidance is hinting towards some potential for fog across portions of the area tonight. Will let the later issuances assess and monitor through the day. && .HYDROLOGY... Issued at 613 AM CDT Sun Jun 23 2024 Heavy rainfall over the previous couple of days has resulted in many area rivers and streams running high or in flood stage. Flooding concerns will last well into the week, with the Mississippi River also continuing to rise. Fortunately, little rainfall is expected into Monday. However, another round of showers and thunderstorms will be possible Monday night into Tuesday. Although some details are uncertain at this time, will need to monitor for any further potential hydro impacts with these storms. Please continue to reference the latest flood statements for additional updates and details. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...EMS AVIATION...EMS HYDROLOGY...EMS