Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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648 FXUS63 KMQT 071907 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 307 PM EDT Tue May 7 2024 .KEY MESSAGES... -Rain showers this afternoon and tonight to bring half an inch to an inch of rainfall to the area. Thunder chances are low, but are most likely (15-30%) along the MI/WI state line. - Multiple passing low pressure systems will keep rain chances in the forecast into early next week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 242 PM EDT Tue May 7 2024 GOES-16 Day Cloud Phase imagery shows high cirrus over the eastern UP and east half of Lake Superior while a cumulus deck moves over the remainder of the region along with weakly convective shower activity along the MI/WI state line. RAP analysis shows a 984 mb low pressure over the ND/SD state line that is vertically stacked and not moving much over the past 3 hours. Rotating around the upper low are shortwaves that are supporting a now- occluded front which is pushing into the UP and causing the shower activity. CAMs show this shower activity overspreading the UP throughout the afternoon and evening. The QPF forecast has gone up a bit with the most recent run of the HREF, with the central UP now seeing slightly over 50% probabilities of an inch of rainfall compared to around 2/3 of an inch at the same probability the last couple of runs. Mean MUCAPE values are still meager, peaking at only around 100 J/kg along the MI/WI state line so the ~15% chance of thunderstorms remains the prevailing forecast along with no severe weather expected. RHs fell into the 20s and 30s ahead of the occluded front in the central and eastern UP this afternoon along with wind gusts around 25 mph, but with cirrus overrunning the region preventing RHs from falling further, expected reductions in wind with time, and the arrival of showers within the next 6 hours, fire weather concerns are low. && .LONG TERM /WEDNESDAY THROUGH TUESDAY/... Issued at 307 PM EDT Tue May 7 2024 Upper air pattern consists of a closed 500 mb low over South Dakota 12z Wed which moves into the upper Great Lakes 12z Thu. A shortwave over northern Saskatchewan 12z Thu dives southeast into the upper Great Lakes late Fri. Get a glancing blow from a shortwave to the south on Thu, otherwise pcpn ends by Wed afternoon. In the extended, the GFS and ECMWF show a 500 mb trough and closed low in the desert sw, a deep trough in the ern U.S. 12z Sat. The trough in the ern U.S. moves to the east 12z Sun with more shortwave energy poised to come into the area with a shortwave over Manitoba. This shortwave dives into the upper Great Lakes 12z Mon and into the lower Great Lakes 12z Tue. Temperatures look to be warming to above normal this forecast period with an active pattern of alberta clipper type systems moving through. One on Saturday, one Sunday. Looks unsettled for this forecast period with some fronts nearby, but no real strong systems to bring widespread rain at this point. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 152 PM EDT Tue May 7 2024 VFR conditions prevail at all TAF sites as showers associated with an occluded front have arrived at IWD and will arrive at SAW/CMX later in the afternoon. As showers intensify, expect the VFR conditions to deteriorate to MVFR this evening and IFR tonight. The worst of the visibility restrictions is most likely at SAW, where a period of time overnight has chances (30-50%) of visibility falling occasionally to around 2SM. Improvement in conditions is expected Wednesday after sunrise, but uncertainty exists in the timing of the ending of showers and the flight categories as moisture departs the TAF sites. && .MARINE... Issued at 307 PM EDT Tue May 7 2024 Easterly winds diminish to below 20 knots tonight before becoming northeast and increasing to 30 knots on Wed into Wed night. North to northeast winds drop below 20 knots on Thu and stay that way into Sun. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Small Craft Advisory until 5 PM EDT this afternoon for LSZ242- 243-247. Small Craft Advisory until 9 PM EDT this evening for LSZ244>246. Lake Michigan... None. && $$ SHORT TERM...GS LONG TERM...07 AVIATION...GS MARINE...07