Area Forecast Discussion
Issued by NWS Twin Cities, MN
Issued by NWS Twin Cities, MN
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730 FXUS63 KMPX 121051 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 551 AM CDT Sun May 12 2024 .KEY MESSAGES... - Elevated fire weather conditions today due to low humidity and marginal winds. - Small chance for a few weak thunderstorms in southern MN and western WI this afternoon. - Mostly sunny the next few days, with a few chances for showers and storms later in the week. && .DISCUSSION... Issued at 304 AM CDT Sun May 12 2024 GOES-16 satellite imagery shows sporadic cloud cover across the region this morning with the densest cloud cover resulting in broken ceilings above the Twin Cities metro. This has unfortunately put an obstacle towards seeing northern lights again this morning, even if it is overall a weaker opportunity than last night. This cloud cover should disperse somewhat as we head towards daylight, however scattered high level cloud cover likely continues for much of the day. An occluded upper level low over eastern Canada will maintain northwesterly flow aloft for Minnesota with a broad and weak trough over the central CONUS will bring a slim chance for a few showers and thunderstorms this afternoon, with southern Minnesota to western Wisconsin the favored targets for now. The SPC HREF shows a cluster of weak cells forming by the afternoon but no legitimate chance at severe weather with moisture remaining locked too far south to access and instability rather weak, with most of the area remaining dry. The main topics for today will be elevated fire weather conditions due to low relative humidity as a symptom of the hottest day of the year thus far with highs in the mid to even upper 80s possible with efficient boundary layer mixing. This sets up a rather quiet period of weather through the next few days with mostly clear skies due to zonal upper level flow and a lack of shortwave impulses to trigger any showers or storms as we await our next synoptic forcing arriving Wednesday into Thursday. Our next chance for showers arrives ahead of an incoming trough with an arrival time somewhere within Wednesday afternoon to evening via a weak surface low spinning up within an area of broad/weak CVA ahead of an incoming trough. Forecast soundings via the GFS/ECMWF show limited instability to work with as well as fairly weak forcing, thus aside from a few rumbles we are not currently expecting any strong thunderstorms. The more likely scenario will be scattered showers arriving Wednesday afternoon and continuing into early Thursday as the trough swings through, followed by another round of generally zonal flow and reliance on shortwaves to produce any further showers as we head towards next weekend. Ensemble guidance is fairly split on overall precipitation amounts, thus forecast confidence after Wednesday is fairly low at the moment which is to be expected given the setup. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 548 AM CDT Sun May 12 2024 The main concerns today will be winds increasing to 10-15kts with occasional gusts to 20kts as they shift from 180-210 to 330-360 throughout, as well as Canadian wildfire smoke entering the region by the afternoon and evening. There is also a slim chance for a few thunderstorms for southern MN and western WI, with around a 20 percent chance for MKT/EAU decreasing for sites more to the north. VFR is expected to continue, however we could be dealing with some visibility reduction from the smoke if we mix enough down to the surface. KMSP...With the addition of the wildfire smoke to the forecast, the chance for storms this far north is even more unlikely as the smoke would hinder development of instability. The chance for -TSRA has decreased from the 06z update which was already too low to include in the actual TAF. /OUTLOOK FOR KMSP/ MON...VFR. Wind N 10-15kts. TUE...VFR. Wind NE 5-10kts. WED...VFR/MVFR, chc -SHRA. Wind SE 10-15kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...TDH AVIATION...TDH