Area Forecast Discussion
Issued by NWS La Crosse, WI
Issued by NWS La Crosse, WI
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023 FXUS63 KARX 111900 AFDARX Area Forecast Discussion National Weather Service La Crosse WI 200 PM CDT Sat May 11 2024 .KEY MESSAGES... - Warmer Sunday with afternoon-evening shower/storm chances (30- 50%). Highs in the 80s with some mid 80s for some river valley/sandy locations. Gusty winds possible with any showers/storms. - Cooler Monday with rain chances lingering (south of I-90-20-60% increasing toward DBQ). - More rain chances for the end of the week with seasonably temperatures Tue-Thu and above normal temperatures Fri && .DISCUSSION... Issued at 144 PM CDT Sat May 11 2024 Overview: Showers and thunderstorms with a cold front pushed through quickly Friday afternoon and evening with rainfall amounts from a 0 to 0.20" and wind gusts for some 25 to 45 mph. Both Rochester and La Crosse had a trace. Rochester gusted to 41 mph and La Crosse to 42 mph at their respective airports. Skies cleared Friday night for a spectacular extended viewing of the Aurora. Today, sunshine continued high clouds moving in from the north and patches of cumulus, especially over central Wisconsin. Temperatures were in the 60s to around 70 early this afternoon. Water vapor satellite imagery, 500mb heights, and lightning showed a trough over the eastern Great Lakes with northwest flow locally and an upstream shortwave over the Northwest Territories/Nunavut and ripple over British Columbia. A closed low pressure system was approaching the Four Corners region with lightning ahead of the trough across parts of CO/NM/TX. The 11.12Z MPX sounding was 50 to 70% of normal with 0.38" precipitable water. Showers could clip parts of west central WI tonight-Warmer for Sunday-Isolated/scattered showers with the cold front Sunday afternoon/night - Gusty winds possible Through Monday, we`ll see the Canadian storm system drop southeast toward James Bay and the closed low over the Four Corner region slowly progress eastward toward the Mid-Mississippi River Valley region, trying to phase, and eventually heads toward IL/IN/OH/KY. The forcing remains off to the north as a warm front moves in overnight and the low level jet strengthens across northern MN into northern WI. There is a general increase in moisture transport into Sunday with stronger magnitudes generally north tonight and east of the area Sunday. Temperatures warm Sunday into the 80s for most. PWAT values do elevate to 100 to 175% of normal ahead of the cold front passage Sunday with forecast soundings showing the moisture mostly in the mid levels or higher. Overnight, a few showers could clip areas north of HWY29. Lapse rates steepen for Sunday 8 to 9.5 deg. C. Theta-e advection increases ahead of the cold front with SBCAPE of 500+J/kg. Deep layer shear values are mostly 25 to 30kts but increase to 35kt for parts of central WI. The HiRes models show isolated to scattered showers and thunderstorms ahead of and with the cold frontal passage; mostly 20 to 50% Sunday afternoon and evening. Due to the steep lapse rates and convective temperatures in the lower 80s could see gusty winds with any showers/storms. Small hail possible with the higher deep layer shear/any stronger storms; parts of central WI or farther east. The progress of the cold front stalls as the closed mid-level low moves into the Plains and tries to phase. This will linger rain chances into Monday south of I90 (20-60% increasing toward DBQ) More rain chances for the end of the week; Seasonable Tue-Thu: Mostly dry Tuesday and Wednesday with periodic rain chances Wednesday through Friday night. The next trough moves through the Mississippi Valley Wednesday night and Thursday. Precipitation could linger into Friday depending on how the stronger energy moves through the trough. Temperatures remain seasonable to mild in the 70s to lower 80s Wednesday through Friday. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1244 PM CDT Sat May 11 2024 A 500 mb shortwave will move across northern Minnesota and northern Wisconsin late tonight and Sunday morning. This might bring some showers to areas north of Interstate 94. Meanwhile, for the TAF sites, it looks like it will mainly bring an increase in high clouds. West and northwest winds will gradually shift to south tonight and southwest on Sunday morning. Wind speeds will be primarily in the 10 to 20 knot range. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. IA...None. && $$ DISCUSSION...Zapotocny AVIATION...Boyne