Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KMPX 260308 AAB

Area Forecast Discussion...UPDATED
National Weather Service Twin Cities/Chanhassen MN
1008 PM CDT Tue Sep 25 2018

.SHORT TERM...(This evening through Wednesday)
Issued at 300 PM CDT Tue Sep 25 2018

Main upper level shortwave working through this afternoon, with rain
moving through much of central MN.  Upstream across the eastern
Dakotas, fairly widespread instability driven showers have popped
up under the trough axis thanks to lapse rates steepening due to
upper level cold air advection.  Did extend some pops into western
MN this evening to account for this activity as it rotates
southeastward with time.  Given the steepening lapse rates, could
see enough instability develop to produce an isolated lightning
strike or two with this activity.

For tonight, generally expect skies to begin clearing out late.  The
showers that work into western MN will likely fizzle tonight, but
leave remnant cloud cover into the morning.  Wednesday will start out
cloudy in spots, but clearing skies are expected as the day
progresses.  Highs tomorrow should warm up to 60-65 degrees,
especially out west where winds become southwesterly late in the

.LONG TERM...(Wednesday night through Tuesday)
Issued at 300 PM CDT Tue Sep 25 2018

The main longer term concerns remain frost/freeze potential
mainly Friday night and Saturday night.

The initial trough exits the area Wednesday night allowing the
next trough and surface cold front to drop southeast across the
CWA for Thursday. Shower chances will spread southeast along and
ahead of the front during this period. Anything that does develop
should be light and affect mainly the northeast portion of the
CWA. Cooler air drops in behind the front into Friday/ Friday
night as high pressure moves in. We expect clear for sky much of
the night with perhaps a bit of high/mid level clouds move in
late. It does look like temperatures will drop off quickly with
the light winds and we should see the first night of a widespread
front across the area with temperatures dropping to the upper 20s
in the far northern areas and low/mid 30s across the south.

The GFS and ECMWF are adamant in drawing in some mid level clouds
over the area for Saturday into Sunday. We may see mainly virga
over the area considering the dry atmosphere initially across the
southern CWA. Better forcing/WAA develops ahead of the next short
wave trough later Sunday into Monday. We may see a thunder threat
if the GFS verifies as it lifts better frontal/baroclinic zone
into southerly MN. The ECMWF is farther south with its frontal
system, keeping the more significant thunder threat farther
south. It does appear another bout of heavy rain may affect the
area during this period as well as this trough moves through. It
still remains questionable how far north into the CWA this will


.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1008 PM CDT Tue Sep 25 2018

Outside of a small potential for patchy fog overnight, VFR
expected through the period. Gusty west winds by late Wednesday
morning will subside quickly Tuesday evening.

KMSP...No concerns.

Thu...VFR. Chc -shra. Winds WNW 15G25 kts.
Fri...VFR. Winds W 5-10 kts.
Sat...VFR, MVFR possible late. Winds SW 10G20kts.




AVIATION...BORGHOFF is the U.S. government's official web portal to all federal, state and local government web resources and services.