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000
FXUS63 KMPX 220530
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1230 AM CDT Mon Apr 22 2024

.KEY MESSAGES...

- Chance of showers across eastern/southern MN and WI Monday
  afternoon/evening and again Tuesday.

- Widespread frost/freeze Tuesday night and early Wednesday.

- The pattern becomes very active with two systems passing
  through at the end of this week and beginning of next week.

&&

.UPDATE...
Issued at 724 PM CDT Sun Apr 21 2024

No changes from the previous forecast. Clear skies continued
across the region this evening, with wind gusts falling off as
we approach sunset. Overnight winds will become more southwest,
with breezy conditions ahead of an approaching cold front. This
front will pass through dry across the west, but bring rain
chances Monday afternoon into Monday evening.

&&

.DISCUSSION...
Issued at 244 PM CDT Sun Apr 21 2024

Elevated fire weather conditions are underway this afternoon
with RH values falling into the teens to mid 20s across the
area. Northwest winds occasionally gusting to 20 mph will ease
just before sunset. High pressure across the central Plains will
slide east this evening, resulting in winds shifting south
overnight with WAA beginning. Light winds across WI should
allow temps to drop into the low to mid 30s overnight, but the
dry air in place will largely prevent frost formation so no
frost or freeze headlines have been issued.

A weakening system tracking east across the southern provinces
of Canada will send a surface warm front through Tuesday. Gusty
southwest winds will develop mid to late morning with some gusts
as high as 35-40 mph in southern MN. Increasing moisture ahead
of a cold front could spark scattered showers over eastern MN
and WI in the afternoon, but PoPs have trended down a bit with
the deeper moisture not reaching this area in time for the
fropa. Cyclonic flow behind the system, a vort max rotating
southeast across the Upper Midwest and steep mid level lapse
rates will likely generate showers and some thunderstorms across
much of the region during peak heating Tuesday afternoon. Any
activity would diminish quickly around sunset.

Another high pressure arrives Tuesday night, bringing light
winds and clear skies. Lows will likely drop to subfreezing
levels again, except maybe across western MN where return flow
may begin late. Freeze warnings or frost advisories will be
needed again early Wednesday.

The longer term then becomes interesting as flow aloft shifts
southwest. Multiple waves will eject from the desert southwest
and track northeast to the Upper Midwest in the Friday to
Sunday/Monday timeframe. A prolonged period of return flow from
the Gulf will set up, and each subsequent system will have
deeper and deeper moisture to work with. In addition, at least
moderately steep mid level lapse rates atop this moist airmass
and strong deep layer shear will create an environment favorable
for severe thunderstorms. The predictability with each system
remains low at this range and the severe threat locally will
depend on the track of any given system, but it`s a possibility
the severe season could ramp up quickly next weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1213 AM CDT Mon Apr 22 2024

VFR conditions continue with light, southwesterly winds through
the AM. Cloud cover will increase from west to east in
association with the approaching cold front. Winds will also
strengthen out ahead of the front, with gusts up to 30kts at
times. Light showers could form for locations further east,
especially over western Wisconsin. These will be fast-moving
rain showers that are primarily MVFR/VFR. Clouds will clear out
from west to east in the late afternoon, providing a break from
the rain until wrap around showers move through on Tuesday.

KMSP...Most likely timing of rain shower development would be
around 20-21z, with showers only lasting a few hours at most.
Wind gusts will increase through the afternoon, before tapering
off again this evening.

/OUTLOOK FOR KMSP/
TUE...Chance MVFR/-SHRA, then VFR late. Wind NW 15-20G30-35kts.
WED...VFR. Wind SE 5-10kts.
THU...VFR. Chance MVFR/-SHRA late. Wind SE 10-15kts.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.

&&

$$

UPDATE...JRB
DISCUSSION...Borghoff
AVIATION...BED