902 FXUS63 KDLH 181807 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 107 PM CDT Mon Mar 18 2019 .UPDATE... Issued at 107 PM CDT Mon Mar 18 2019 Updating Aviation section below for the 18Z TAF update. UPDATE Issued at 1013 AM CDT Mon Mar 18 2019 We have cancelled the Dense Fog Advisory since visibility has improved in Cass County. Updated POPs to reflect ongoing flurries in the Arrowhead and portions of north-central Wisconsin. && .SHORT TERM...(Today through Tuesday) Issued at 344 AM CDT Mon Mar 18 2019 A mix of clear and cloudy skies have developed over the Northland, along with some patchy fog in spots as well, particularly in areas of enhanced radiational cooling due to the clear skies. Radar imagery is showing some enhanced returns between International Falls and Hibbing as a mid-level shortwave impulse continues to sweep through the region. The high-resolution models have struggled simulating this reflectivity. Area webcams in those areas show a burst of light snow falling, so have increased to chance POPs and increased the snow amounts as well. Snow accumulation along the international border region south to Duluth could see a few tenths up to a half inch of accumulation with this snow. These chances of snow will slowly diminish after sunrise today as surface high pressure builds across the central Great Plains states. The high pressure ridge, and associated subsidence per the Thaler QG omega progs, should bring a period of partly to mostly sunny skies over much of the Northland. This should allow highs today to warm to the middle to upper 30s across the Northland, slightly above average for this time of the year. The influence from the high pressure will be brief as a compact shortwave trough will dive southward over the Dakotas late this afternoon through tonight, which will increase lift over the region, supporting more chances of precipitation. For now, we have POPs increasing over Koochiching county late this afternoon, mainly in the form of light rain, mixing with snow this evening, and expanding southeastward. These POPs may be a little too early as the NAM and the RAP model soundings show a good bit of dry air in the low-levels, which could inhibit the onset of the precipitation. However, there is better agreement that this dry air will eventually be overcome this evening and overnight due to top-down saturation, so have more widespread small POPs over northeast Minnesota. Once again, a coating to perhaps a few tenths of an inch of snow will be possible. Cloud cover will be a bit more robust during the day Tuesday as some warm air advection will increase on southwest flow. Highs on Tuesday could warm well into the 40s over northwest Wisconsin, with lower 40s elsewhere. For now, there isn't a strong signal for precipitation for Tuesday, but cannot rule it our completely. Confidence is much higher for some partly to mostly cloudy skies. .LONG TERM...(Tuesday night through Sunday) Issued at 231 AM CDT Mon Mar 18 2019 The extended period continues to look mostly dry, with a warming trend into next weekend. A shortwave may bring some light snow or light rain to far northern Minnesota into northern Wisconsin Tuesday night and over a portion of far northeast Minnesota Wednesday. Any accumulation will be quite light. After this time, an upper ridge will slowly move east reaching the Northland Friday/Friday night. The ECMWF remains slower moving the upper ridge into the area and also moving it east of the area over the weekend. Most areas will be dry Wednesday into Saturday. High temperatures during this time will be in the lower to middle forties on Wednesday but warm to into the lower to middle fifties on Saturday. Overnight lows will still drop below freezing each night, slowing the snowmelt some. The GFS continues to push the upper ridge east Saturday night into Sunday quicker than the ECMWF. The GFS then brings an upper trough over the region on Sunday along with a surface low. Light rain will be possible if the GFS solution ends up verifying. However, the upper ridge may end up being tougher to displace than the GFS is forecasting. We do have chances for precipitation Saturday night into Sunday for now. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 107 PM CDT Mon Mar 18 2019 A cumulus field over the area as of issuance time has produced primarily VFR conditions, though a few sites are reporting MVFR ceilings with rain/snow showers, which should be temporary in nature. This cumulus field should dissipate or become all VFR by 22z. A front will move through the area after 00z, bringing an area of initially VFR clouds that slowly deteriorate to MVFR with a small chance of showers for KINL and KHIB after 06z. The MVFR ceilings should become scattered and return to VFR betwee 13z and 17z. && .PRELIMINARY POINT TEMPS/POPS... DLH 36 24 41 29 / 30 10 10 10 INL 39 23 40 28 / 30 20 20 20 BRD 36 23 39 27 / 0 10 10 0 HYR 39 21 44 28 / 10 0 0 10 ASX 40 22 44 29 / 10 10 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ UPDATE...LE SHORT TERM...JTS LONG TERM...Melde AVIATION...LE