Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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280 FXUS63 KMQT 010659 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 259 AM EDT Sat Jun 1 2024 .KEY MESSAGES... - Scattered showers continue across the west through tonight with a few embedded thunderstorms. Locally heavy rainfall >1" possible, especially with thunderstorms. - Frequent opportunities for showers and thunderstorms over the next 7 days. - Above normal temperatures through the first half of next week, then turning cooler. && .SHORT TERM /THROUGH TONIGHT/... Issued at 410 PM EDT Fri May 31 2024 Only minor forecast updates were needed today with sunnier skies allowing for slightly warmer temperatures approaching 80F. Deeper mixing also allowed for somewhat stronger winds, but overall the fire weather forecast was spot on across the east with RH dipping to around 25% and SSW winds of 10-15 mph with gusts to 20mph. The only exception was the Newberry RAWS which is reporting a dew point 11- 17F lower than all surrounding observations raising questions about how representative the observation is. On the other side of the Peninsula, an area of rain/rain showers lifted northeast across our western tier of counties for most of the day. While no thunder has been reported, CMX reported a brief period of heavy rainfall as it moved overhead. Coverage is currently waning suggesting a general lull head of the next wave this evening. As of 355 PM our radar started picking up the frontal boundary extending southeast from Big Bay. Looking ahead through tonight, the frontal boundary is expected to slow and eventually stall tonight. As the boundary stalls, the nocturnal LLJ ramps up to around 35 kts as it noses into our area this evening. This disturbance and the associated area of of showers and embedded thunderstorms is already showing up on regional radar in the vicinity of Minneapolis. CAPE is insufficient for severe concerns, but pwat values >1 inch (approaching the 90th percentile) and potential for multiple rounds of rain suggests a chance for locally heavy rainfall and perhaps patchy fog too. 12z HREF PMM guidance paints a stripe of heavier QPF between Watersmeet and L`Anse, which is primarily instigated by NAMnest and HRW NSSL guidance. However, it`s worth noting that most other guidance is further west roughly between Ironwood and Copper Harbor. Fortunately, river levels remain low and flooding concerns are limited to ponding in poor drainage areas. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 259 AM EDT Sat Jun 1 2024 Expect dry conditions to return to the U.P. Sunday as the cold front leaves the far east during the early morning hours and weak sfc ridging returns to the area. With sfc ridging and zonal flow in the mid-levels over the area during the day Sunday, expect a diurnal cu field to develop over Upper MI by the afternoon hours as troughing and warm air advection begins to make its way back over the area by early Sunday evening. With PWATs around 0.75 inches, there is an outside chance (around 10%) that we could see a stray lake breeze induced rain shower or two over the central and east late in the day. However, given the high pressure ridging at the sfc, the dry air in the PBL should eat away any moisture that falls out of the cu field. Should anything make it to the sfc, expect short-lived sprinkles to light rainfall. Moving into Sunday night, expect the mostly clear skies to progressively give way to clouds as a cold front bringing showers and storms approaches from northern MN. The most recent NBM run has pushed back the timing of the showers and storms arriving over the western U.P. late Sunday night and Monday morning. In addition, the model consensus shows little, if any CAPE to work with and 0-6 km bulk shear values generally less than 30 kts. Therefore, severe weather is not expected at this time over the western U.P. Monday and Monday evening. The cold front will slowly crawl from west to east early this week across our area before weak high pressure ridging returns to the U.P. Tuesday. As this occurs, expect rain showers and thunderstorms across our area from Monday into early Tuesday morning. The low behind the cold front early this upcoming week will lift towards Hudson Bay with time before being phased with an amplifying Clipper low by the middle of next week. Strong warm air advection from the Gulf is brought over our region ahead of the cold front of the low`s arrival Tuesday and Tuesday night. Therefore, expect high temperatures Tuesday to break into the 80s across the interior areas. I could see dewpoints and RHs being lower than what`s currently being predicted by the NBM for Tuesday; if there is less cloud coverage than what`s currently predicted (partly cloudy skies at the moment), then mixing in the boundary layer will be greater, and thus dewpoints and RHs will be lower (I would wager their is around a 50% chance of this occurring at this time). As it stands now though, RHs are not expected to dip below 50%. The cold front of this low begins moving into the area late Tuesday afternoon/early Tuesday evening over the far west, with showers and thunderstorms moving over the rest of the U.P. Tuesday night through Wednesday. Once the cold front passes through, the vertically- stacked low sits over northern Ontario and brings cold air advection across our area. As this occurs, expect additional weak shortwaves rotating around the parent low to move across the Upper Great Lakes, bringing additional rain showers and possibly (15% chance) a thunderstorm or two back across the area to finish out the work week. Thus, along with the scattered rain chances, expect to see below normal high temperatures late next week; this is reflected well in yesterday`s 12z run of the EFI for the daytime Friday, with some of the ensemble runs showing highs in the 10th percentile or cooler of climatology. Therefore, we could see some unseasonably cool daytime temperatures come late next week. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 129 AM EDT Sat Jun 1 2024 Delayed onset of MVFR (possible IFR) conditions at IWD/CMX until the 10-14Z time frame as showers continue to filter into TAF sites in association with a cold front. Thunder potential for the overnight has diminished and will not be included in fcst. Until deterioration later this morning, VFR will be the prevailing flight category at IWD and CMX. Elsewhere, flight restrictions are not expected at SAW and VFR will be the predominant flight category for duration of TAF period. Meanwhile, winds will generally be light and variable with little to no impact. && .MARINE... Issued at 259 AM EDT Sat Jun 1 2024 Light winds of 20 knots or less continue across Lake Superior until a cold front crawling eastwards across the lake brings southeasterly winds of 20 to 25 knots over the higher elevation platforms and the Lake Superior southerly nearshores Monday. Behind this, expect a return to light winds Tuesday, before stronger winds could possibly return with the coming of a second cold front Tuesday night into Wednesday; expect gusts to around 20 knots from the southwest over the western half. Moving into the latter half of next week, we could see higher winds from the northwest as cold air advection from Canada works in tandem with weak shortwaves dropping down across the area to mix stronger winds aloft to the lake`s sfc. Thunderstorms are possible across the south central and eastern portions of Lake Superior this afternoon and evening as a weak cold front moves through. Thunderstorm chances return from Sunday night to early Tuesday morning as a second cold front slowly makes its way from west to east across the lake. Additional thunder chances return late Tuesday and continue through Wednesday as yet another cold front pushes through from west to east across the lake. No severe weather is expected from these storms. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ SHORT TERM...EK LONG TERM...TAP AVIATION...TDUD MARINE...TAP