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Office: MPX

FXUS63 KMPX 162210

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
510 PM CDT Mon Jul 16 2018

.UPDATE...For 00Z Aviation discussion below


.SHORT TERM...(This evening through Tuesday)
Issued at 304 PM CDT Mon Jul 16 2018

There is nothing significant to be concerned about for the next 24
hours. Cyclonic flow across the Upper Midwest is producing gusty
winds this afternoon north of I-94, but all of the stratocu is
confined to northern MN and Canada, making for a beautiful day
locally. Dry air and light winds tonight will allow for efficient
radiational cooling with lows in the mid 50s to lower 60s, although
a band of clouds developing overnight could prevent temps from
cooling as low as the dew points this afternoon.

.LONG TERM...(Tuesday night through Monday)
Issued at 304 PM CDT Mon Jul 16 2018

Main focus of the long term period is the strong low pressure system
expected to impact the area late Wednesday night through Friday. The
remainder of the period looks quiet with near normal temperatures.

By Tuesday night, the surface high will be gradually progressing
east of our area.  Meanwhile, a strengthening upper level shortwave
will emerge from Wyoming and surface cyclogenesis is expected across
western South Dakota from Tuesday night into Wednesday.
Strengthening southeasterly winds on Wednesday will advect higher
dew point air into the region, before becoming more easterly
Wednesday night, serving as a precursor to the approaching low
pressure system. Initial showers will likely move into far western
Minnesota as early as Wednesday night, as the strengthening low is
expected to move east from South Dakota into southwestern MN by
Thursday morning.

PWAT values should surge ahead of the system to near 2", and with
limited CAPE but ample synoptic scale ascent, Thursday will bring
widespread and long duration rains in the 1-2" range for most, but
localized amounts in excess of 2" are also anticipated.  Due to the
limited instability with this system, did lower the chance for
thunder in the forecast.  Thursday will likely be 5-10 degrees
cooler than normal given the long duration rain.  The system will
slow as it heads into Wisconsin by Friday, keeping us with wrap
around rain showers and breezy northerly winds for much of the day

This system will move off over the Great Lakes by Saturday and we'll
remain to the east of the next possible system that will be slowly
moving east across southern Canada into early next week.  Other than
the chance for some early morning rain lingering on Saturday, the
weekend looks to be dry with partly cloudy skies and temperatures in
the low 80s.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 511 PM CDT Mon Jul 16 2018

Few-scattered mid/high clouds will filter across the area through
the period, with VFR expected throughout. Winds light NW/N/NE.

Continued high confidence in the TAF with no concerns.

WED...VFR. SE Wind 5-10 kts.
THU...MVFR/SHRA/TS. Wind SE 10 kts.
FRI...MVFR/SHRA. Wind NW10-15kts.





Office: DLH FXUS63 KDLH 162359 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 659 PM CDT Mon Jul 16 2018 .SHORT TERM...(This evening through Tuesday) Issued at 259 PM CDT Mon Jul 16 2018 Quiet weather is expected through Tuesday, with a ridge of high pressure building into the area at the surface and northwest flow aloft. Cumulus over the borderlands this afternoon should dissipate around sunset. The very deep mixing today has caused winds to be very gusty, with gust speeds in the 30-35 mph range for several locations so far this afternoon. These should diminish by early evening as well. This will leave us with clearing skies this evening, rising pressures overnight and very light winds, which should produce good radiational cooling conditions overnight. Have gone with min temperatures in the bottom 10 percent of guidance, with lows in the 40s for much of the Arrowhead, with low 50s elsewhere. On Tuesday the ridge slides slowly east across the area, keeping our winds light even as we get another day of deep mixing. This should cause temperatures to be warmer than most guidance, and have gone with highs in the mid- upper 70s most locations. The deep mixing does not have strong winds to tap into aloft though, so it will not be as windy tomorrow as it has been today. .LONG TERM...(Tuesday night through Monday) Issued at 259 PM CDT Mon Jul 16 2018 The Northland will be getting a pattern change later this week, which could bring a couple days of rain and some thunder. High pressure over the Great Lakes in the middle of the week will provide the Northland another warm and humid day. We are forecasting mostly sunny skies, but we may need to increase cloud cover because of what could be cirrus blowing over the Northland from the west from what will be the region's next weather maker. Projections continue for a deep and slow moving low pressure system to develop in the Northern Plains during the middle of the week and move into the northern/western Great Lakes during the Thursday and Friday timeframe. This low will likely bring abundant moisture and wetting rains to the region, but the threat of thunder is more difficult to discern. The GFS and European have a vertically stacked low tracking east just to our south Thursday through Friday, while the Canadian has less phasing with the surface low and upper level trough/low. Cloud cover and cool easterly flow from Lake Superior will likely limit instability for storms, but forcing from the low and frontogenetical bands could develop some thunder. Therefore, lowered the threat of thunder in comparison to chances of rain. For any storms that do develop, the threat of severe weather will likely be very low. At this time, anticipate widespread rainfall of a half to full inch, with the heaviest amounts likely from central MN to areas of WI well south of Lake Superior where the chances of thunderstorms will be better than areas farther north in Minnesota and near Lake Superior. The low will shift east out the region Saturday, and the Northland will get warm, but drier northerly flow. Expect partly sunny skies with scattered cumulus, and there could be sprinkles and light showers during the afternoon and early evening because of daytime heating and sufficient moisture in the air. High pressure should return to the Northland Sunday and provide another sunny day. Another low and cold front could bring thunderstorms back to the Northland late Sunday night and Monday. && .AVIATION...(For the 00Z TAFS through 00Z Tuesday evening) Issued at 656 PM CDT Mon Jul 16 2018 A weak trough will move through the Northland overnight, with some scattered to possibly broken stratocumulus clouds. The best chance for seeing a period of broken cloud cover would be in the north. The remainder of the area should see little cloud cover. VFR conditions are expected throughout the period. && .PRELIMINARY POINT TEMPS/POPS... DLH 51 74 53 79 / 0 0 0 0 INL 45 74 50 82 / 10 0 0 0 BRD 52 77 56 80 / 0 0 0 10 HYR 49 77 51 80 / 0 0 0 0 ASX 52 73 52 80 / 0 0 0 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ SHORT TERM...LE LONG TERM...Grochocinski AVIATION...DAP