Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 300832
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
332 AM CDT FRI SEP 30 2016

.SHORT TERM...(Today and tonight)
Issued at 332 AM CDT Fri Sep 30 2016

Cut-off H5 low that drifted down into KY yesterday is already
starting to lift back to the NNW this morning. Biggest implication
for us is that the low stratus looks to return from the east faster
than initially indicated, with sky grids increased considerably this
afternoon in western WI/eastern MN and overnight for western MN. 925-
850 RH off the GFS/NAM/RAP shows cloud cover currently over SE WI
ending up in eastern SD by Saturday morning. Of interest though is
that the NAM in particular shows a wedge of dry air dropping down
from Lake Superior tonight, with skies actually clearing out some in
western WI tonight as the stratus is heading for SD.  Given the
expected cloud cover, low 70s are unlikely again today out in
western WI.

Other issue more for this morning is a batch of low stratus coming
down off of Lake Superior.  The HRRR shows this cloud cover getting
down to about the Twin Cities/Wilmar in the for of fog/low stratus.
Though this may result for a cloudy morning for much of central MN,
this looks to mix out by mid-late morning with a brief window of
sunny skies in the afternoon before cloud cover arrives from the
east.

Last change made in the short term was to keep the Eau Claire area
dry through 12z Saturday. CAMs and deterministic models alike keep
the MPX area dry, with any rainfall Friday night confined to eastern
WI where moisture on the 290-305k isentropic surfaces.

.LONG TERM...(Saturday through Thursday)
Issued at 332 AM CDT Fri Sep 30 2016

The period begins with a stubborn upper level low lifting slowly
northward across Indiana. Considerable cloudiness will occur
across the FA in the morning along with a few showers from the
southeast corner of MN through KEAU. The cloudiness should begin
to breakdown from the northeast in the afternoon as drier air
spreads in along with the upper level low beginning to drift east.
This leaves a horseshoe of higher cloud cover curving from
western MN through IA to eastern WI. The cloudiness will breakdown
Saturday night leaving us with a fine early fall day on Sunday.
High temperatures this weekend will be very close to seasonal
values with lows about 5 degrees above normal.

We have had a little bit of a roll reversal for next week between
the EC and GFS with regards to the weather system impacting the
FA in the Tuesday through Thursday period. The EC continues to
inch forward a bit on the leading edge of the rain on Tuesday
while the GFS is looking more like earlier runs of the EC on
keeping rain out of the Twin Cities until Wednesday afternoon. The
Canadian would also keep rain out of the local area until
Wednesday afternoon.

One of the differences noted is that the EC has more of a
positively tilted upper wave while the GFS and Canadian are more
negatively tilted. At this point, we allowed small pops into
western MN on Tuesday with the small pops working across eastern
MN and western WI Tuesday night. This will be too fast if the
latter solutions are correct. Another item noted is the strength
of the low level moisture transport Tuesday night and early
Wednesday across western MN. This area will likely see the most
rain from this event with amounts of a half inch to one inch
likely. The long term closes out with a cold front pushing east of
the FA with a breezy southwest wind occurring on Thursday.

High temperatures early next week will continue to be close to
seasonal normals. However, highs will trend downward thereafter,
with readings only in the middle 50s to lower 60s expected on
Thursday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1143 PM CDT Thu Sep 29 2016

Mainly clear skies and light winds are expected for the first half
of tonight, but we are watching an area of low stratus that is
starting to expand west-southwest. It is most likely at KSTC and
KAXN...but also possible at KMSP and KRNH. 300-600ft ceilings are
being observed with these clouds.

KMSP...

We are changing are tune about a clear morning. The low stratus in
northern WI and northern MN is making good progress W-SW, and
these 400-700ft ceilings could be close or over KMSP by sunrise
if the trends continue.

/OUTLOOK FOR KMSP/
Sat...VFR. Wind ENE at 5 kts.
Sun...VFR. MVFR possible. Wind NE at 5 kts.
Mon...VFR. Wind SE at 5-10 kts


&&

.MPX Watches/Warnings/Advisories...
WI...None.
MN...None.
&&

$$

SHORT TERM...MPG
LONG TERM...RAH
AVIATION...CLF


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