Area Forecast Discussion
Issued by NWS Duluth, MN
Issued by NWS Duluth, MN
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945 FXUS63 KDLH 181747 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1247 PM CDT Sat May 18 2024 .KEY MESSAGES... - Marginal Risk for severe storms this afternoon and evening with large hail up to quarter size and gusty winds being the biggest concern - Short dry spell Saturday night and Sunday morning before our active weather pattern returns next week with multiple periods of rain through the week. && .DISCUSSION... Issued at 521 AM CDT Sat May 18 2024 A round of scattered showers and isolated thunderstorms is moving through the area this morning as a low pressure system and cold front advance through the area. An upper level shortwave will also move across the area this afternoon, and as it interacts with the front, we should have a decent trigger for thunderstorms. How strong the storms get depends on just how much instability we can build ahead of the front. Deep layer shear will be sufficient for some isolated strong to severe storms, though I do not expect this to be a widespread threat. This will also be confined to along and east of the cold front, depending on where it is located by early afternoon. It will be warm and humid ahead of the front, with highs getting into the low 80s for northwest Wisconsin and 70s for northern Minnesota. These temperatures will be well above normal, but nowhere close to record highs, which are around 90. Behind the cold front tonight and Sunday morning I expect a period of quieter weather with cooler temperatures, with highs in the 70s. A ridge of high pressure will slide across the area, producing lighter winds as well. Our next chance of precipitation moves in Sunday afternoon and night as yet another shortwave and surface low system moves towards the area, and then across the area on Monday, bringing a higher potential (60% or more) for more than a quarter inch of rainfall, especially over northwest Wisconsin, closer to the surface low track. Much of the area will get a break in precipitation Monday night. Another round of precipitation as a fairly potent shortwave and a strong surface low moves from the KS/NE high plains north- northeast across IA and then across WI Tuesday through Wednesday. For now there is fairly decent ensemble agreement on this general pattern, and it appears most members bring the surface low to the southeast of the forecast area. This should bring mainly rain/rain showers and less thunder, but the farther north the track, the more potential we will have for thunderstorms and perhaps even severe weather. The more southerly track for now favors cooler temperatures for Tuesday and Wednesday as well. Lingering smaller precipitation chances linger Thursday through Saturday along with cooler temperatures in the wake of the stronger mid week system. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1247 PM CDT Sat May 18 2024 A cold front is passing through this afternoon. At DLH, wind direction is expected to become more westerly through the next hour or two before direction settles at westerly later in the afternoon. The chance for thunderstorms at DLH has diminished considerably. Maybe a 5-10% chance that a storm could erupt close to the terminal within the next hour and a half or so, but more likely to remain dry at this point with storm initiation further west. Otherwise, blustery winds continue through early evening before weakening. VFR conditions expected through the period. Elsewhere in MN, anticipating dry VFR conditions with only the slightest chance for a pop-up shower this afternoon since the cold front has passed already. At HYR, there is about a 30-40% chance for a thunderstorm just before the cold front passes. Latest models suggest storms will develop further east, but there remains a possibility that a storm could impact the terminal. Expect winds to shift to westerly at HYR this afternoon and decrease in speed overnight. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 521 AM CDT Sat May 18 2024 Northeast winds today will switch around th the west-southwest and increase in the wake of a cold front. These stronger winds are expected to cause hazardous conditions for small craft from late this morning through the afternoon and evening before diminishing again overnight tonight. The strongest winds are expected along the South Shore and around the Twin Ports. The southwest winds continue on Sunday, and we may get a period of hazardous conditions once again Sunday afternoon, but this time along the North Shore north of Grand Marais. Winds begin to switch around to the southeast and then east Sunday night, and then northeast by Monday morning. For now it does not appear winds will be strong enough for hazardous conditions on Monday. For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. MARINE...Small Craft Advisory until 10 PM CDT this evening for LSZ121- 148. Small Craft Advisory from 4 PM this afternoon to 10 PM CDT this evening for LSZ144>147-150. && $$ DISCUSSION...LE AVIATION...JDS MARINE...LE