Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 211708

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1208 PM CDT SAT MAY 21 2016

.SHORT TERM...(Today and tonight)
Issued at 433 AM CDT Sat May 21 2016

Today will be one of the nicest weather days we will likely see
all year. The main change from what we saw yesterday is today will
feature more sunshine, which will allow highs to be 2 to 5 degrees
warmer than what we saw yesterday. Really, the only major change
from guidance that was needed was to once again go lower with
dewpoints as deep mixing will again promote dewpoints falling back
into the 30s and 40s this afternoon.

Tonight, the upper ridge axis will move overhead, which means more
clear skies. In addition, the arrival of the upper ridge will also
help push the surface high back into the Great Lakes, with return
flow setting up across western MN by the end of the night. Still,
winds will be fairly light and you add in the clear skies and dry
atmosphere and we will again see pretty strong temperature drops
with lows again falling back a good 25 to 30 degrees from our
afternoon highs.

.LONG TERM...(Sunday through Friday)
Issued at 433 AM CDT Sat May 21 2016

Sunday will be the last day with dry weather before showers and
thunderstorms move out of the Dakotas and into western Minnesota
by Sunday night and spread eastward across the state and into
Wisconsin on Monday.

By Sunday morning, the forecast area will be directly underneath
the upper ridge. The west coast trough will slowly move into the
Dakotas during the day Sunday and by 12z Monday, Minnesota will
find itself on the back side of the ridge with southwesterly flow
advecting moisture from the central and southern Plains into the
area. A cold front and surface low will track east toward
Minnesota on Sunday as well, but the system will weaken as it
approaches. The trough will provide cooling aloft and that
combined with moisture advection will create 500-1000 J/KG of
MUCAPE to go along 25-35kts of deep layer shear. This is the
reason for SPC`s Marginal Risk for severe weather in far western
Minnesota Sunday night and across the entire forecast area on
Monday. While thunder looks promising, the threat for severe
weather will likely be limited by cloud cover and the lack of deep
instability. The shear also only suggests weakly organized
convection. There should be a lull, at least in terms of
widespread rain coverage on Tuesday, before another wave is
ejected out of the base of the long wave trough in the southwest
US. The shortwave moves north and passes through the forecast area
on Wednesday. A couple more disturbances embedded in that
southwest flow move up this way THU-FRI, which is the reason we
carry showers/storms in the forecast all the way through the week.
The next 7-10 days resemble an active summer pattern with several
shots at moderate to heavy rain, but with a fairly low severe
weather risk overall.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1205 PM CDT Sat May 21 2016

VFR and no aviation concerns through tonight. Sunday morning will
see increasing south-southeast winds along with gusts of 20-24 kts
in western Minnesota.


No additional concerns with increasing south-southeast winds of
12-14 kts by the end of the taf period.


MON...Mainly VFR. TSRA likely with MVFR possible. Wind S 10-15 kts.
TUE...Mainly VFR. Chc TSRA/MVFR. Wind S 5 kts.
WED...Mainly VFR. Chc TSRA/MVFR. Wind light and variable.


.MPX Watches/Warnings/Advisories...


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