Area Forecast Discussion
Issued by NWS Duluth, MN
Issued by NWS Duluth, MN
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311 FXUS63 KDLH 062341 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 641 PM CDT Mon May 6 2024 .KEY MESSAGES... - Rain moves into the area late tonight with strong storms potential Tuesday Afternoon with the chance for gusty winds and small hail. - Drier conditions arrive Wednesday with the chance for a potent lake breeze each day. - Rain chances increase late this week and into the weekend due to a few shortwaves dropping out of Canada. && .DISCUSSION... Issued at 239 PM CDT Mon May 6 2024 Short Term: Beautiful Spring conditions are in place across much of the Northland and will persist into this evening. Highs will top off in the upper 60s (near the lake) to low 70s (inland) with mostly clear skies and a light SE wind to top it all off. Late this evening and into early tomorrow is when our weather will drastically change for the messier. At the synoptic level, a negatively tilted upper level trough will exit the Southern Plains this afternoon leaving much of the Plains and Great Lakes in strong SW flow at 500mb. This will contribute to the development of sub 980mb surface low across the Northern High Plains. While the surface low itself wont be close to our CWA, an occluded front that will stretch from Dakotas through Minnesota and down into the Southern Great Lakes will be the focus of our precipitation tomorrow morning. The front will be orientated NW-SE and be moving perpendicular to its orientation towards the NE. The frontal boundary will give us rain showers starting in Central Minnesota before overspreading towards NW Wisconsin and towards the Arrowhead. Rainfall at times could be heavy with 6hr rainfall totals reaching upwards of 0.5 along the I-35 corridor and up towards the North Shore. This band should slowly weaken and drift towards the US/Canadian Border through the day allowing for some clearing behind it through the afternoon. Some instability will develop with up to 1000J/kg of MUCAPE developing in NW Wisconsin with lesser amounts as one heads further NW towards the MN/WI border and into Minnesota. With bulk shear in the 20-40kt range, we could see some convective elements with any storms that can fire Tuesday Afternoon. The SPC has placed the entire area in a General Thunderstorm Risk with a few of our counties in NW Wisconsin in a marginal risk (level 1 out of 5). Those counties would have the best chance of seeing stronger storms capable of gusty winds and small hail (20-30%). Should we see slightly more clearing, theres a non- zero chance that we get cold air funnels due to the presence of adequate 3CAPE and low-level vorticity. Extended Range: By Wednesday morning most of the precipitation will have ended as the system finally leaves our region. Following its exit, our region will be placed in a northerly flow in tandem with another system developing across the Southern Great Lakes late on Wednesday. Within this northerly flow, a strong lake breeze will form with temperatures near the lake in the upper 40s/lower 50s while inland areas will see their highs closer to 62-67 degrees. Thursday will be similar with temperatures likely a few degrees warmer than the prior day. As we head into the weekend, a series of shortwaves will move SE out of Canada and into our vicinity. We should see elevated precipitation chances for each of the days with no specifics set in stone at this point. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 624 PM CDT Mon May 6 2024 VFR conditions persist until early Tuesday morning, when a system bringing rain to the region will cause lowering ceilings and light to moderate rainfall will lower visibilities at times. A strong low level jet will lead to some LLWS in the early morning hours, but will end once precipitation starts. Primarily, MVFR conditions are expected, but conditions could lower to IFR at times. Thunderstorms will become embedded in the rain showers tomorrow afternoon - with only a marginal chance for severe storms in Burnett, Washburn, and southern Sawyer counties in Wisconsin. Winds will remain strong throughout the TAF period, with gusts ranging from 20-30 kts. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 624 PM CDT Mon May 6 2024 Northeast winds are beginning to increase out on Lake Superior this afternoon, with Small Craft Advisories going into effect this afternoon as both winds and waves increase. A low pressure system advancing toward the area will push rainfall into the area overnight tonight and Tuesday, keeping the trend of increasing winds and waves going through the daytime on Tuesday. Winds may diminish for a short time this evening before increasing again during the early morning hours of Tuesday, but the longer fetch of the wind will keep waves building. We may have a period on Tuesday from late morning through the afternoon where we may get some gale force gusts along the North Shore north of Two Harbors. Currently, the certainty on this is not very high and this potential may not affect a very large area or for very long, so have not upgraded to a Gale Warning at this time. After Tuesday, northeast winds continue into Wednesday and even Thursday before backing into the north. We may need additional Small Craft Advisories for all or parts of the lake and for the time frame through Thursday. 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 from 7 AM Tuesday to 4 AM CDT Wednesday for LSZ140-147-150. Small Craft Advisory from 4 AM Tuesday to 4 AM CDT Wednesday for LSZ141-142. Small Craft Advisory until 4 AM CDT Wednesday for LSZ143>146. Small Craft Advisory from 10 AM to 4 PM CDT Tuesday for LSZ148. && $$ DISCUSSION...LE/KP AVIATION...KML MARINE...LE