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000
FXUS63 KMPX 161747
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1247 PM CDT Tue Apr 16 2024

.KEY MESSAGES...

- Strong winds today, with easterly gusts of 40-50 mph likely.
  (potentially higher during showers and thunderstorms).

- Widespread rain will spread across the area today, with
  showers and thunderstorms continuing through Wednesday
  morning.

- Below-normal temperatures Friday through Sunday with highs in
  the 40s and 50s expected. Sub-freezing lows are likely.

&&

.DISCUSSION...
Issued at 313 AM CDT Tue Apr 16 2024

Radar remains clear early this morning, despite a decent elevated
mixed layer with lapse rates 7-8 C/km. This is due to lack of
forcing at present. The EML will dissipate as an upper level
shortwave approaches from South Dakota. This will
drive warm air advection and increase the forcing required for
showers to begin in southwestern Minnesota around the morning
commute. While forcing will now be increasing, lapse rates and any
substantial instability will be missing. Things will translate
northeastward, with showers and thunderstorms reaching the Metro by
lunchtime, if not sooner. Early afternoon soundings lack CAPE, but
remain saturated. Hi-Res models continue to depict widespread rain
with embedded bands of heavier showers and thunderstorms as the
system moves through.

By this evening, RAP model soundings at Albert Lea depict the
reconstruction of the elevated mixed layer with decent elevated CAPE
around 800 J/kg. Tracing this to the surface, CAPE is cut in half
and CIN triples. If we are able to overachieve on clearing and rid
low level CIN this evening, the helicity is there to support the
SPC`s 2% tornado risk across far southern Minnesota. The threat
remains conditional on being able to recover CAPE and clear CIN.

On a broader scale, the stronger instability isn`t forecast to get
farther north than the I-90 corridor. Regardless, a few embedded
thunderstorms are likely across all of southern and central
Minnesota and western Wisconsin. Guidance continues to show 1-2" QPF
for southern Minnesota and western Wisconsin, with higher end totals
more likely to the south. Isolated amounts in excess of 2" are
certainly possible in areas that are impacted by multiple rounds of
thunderstorms.

Taking a step back from precipitation, the low-level jet with this
system is impressive and is the reason for a (nearly) area wide Wind
Advisory this morning through this evening. A tightening
pressure gradient will likely squeeze out peak gusts of 40 to
45MPH. Adding showers and thunderstorms on top of the already
potent LLJ will only act to bring the stronger gusts down to the
surface more frequently. Winds should subside and become
northwesterly overnight as the surface low moves overhead. Winds
will rebound again on Wednesday, but to a lesser extreme (peak
gusts to 30-35MPH).

High pressure will move in by later in the week, with much cooler
temperatures taking place. Highs on Thursday will still be in the
50s, but only in the 40s on Friday and Saturday. Friday and Saturday
night lows will dip below freezing for most. This is around 5-10
degrees cooler than normal, but will feel much cooler than that due
to our recent warm temperatures. No significant precipitation is in
the forecast beyond Thursday, but temperatures will quickly return
to normal.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1239 PM CDT Tue Apr 16 2024

Ceilings have remained VFR/MVFR through early this afternoon,
but expecting them to come down through the period. A broad area
of showers with embedded thunderstorms will continue across the
region with IFR/LIFR cigs/vis expected with stronger showers and
storms. Winds are also quite strong out of the east with gusts
of 30-40kts and higher gusts possible with any of those stronger
showers and storms. Additionally, LLWS could prove to be an
issue, particularly across eastern Minnesota/western Wisconsin
as a strong LLJ ramps up this evening. Winds will eventually
become north/northwesterly by tomorrow morning for all except
KEAU.

KMSP...A brief break in the heavier rain and thunderstorms is
expected to last for the next two hours or so before another
round pushes northward out of Iowa. By this evening, we`ll
likely see another break before another round of thunderstorms
moves through early Wednesday with IFR/MVFR cigs/vis
continuing with northwest winds 20g30kt.

/OUTLOOK FOR KMSP/
THU...VFR. Wind W 15-20G30 kts.
FRI...VFR. Wind WNW 20G30 kts.
SAT...VFR. Wind NW 10-15g25 kts.
&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...Wind Advisory until 7 PM CDT this evening for Anoka-Blue Earth-
     Brown-Carver-Chippewa-Dakota-Douglas-Faribault-Freeborn-
     Goodhue-Hennepin-Kandiyohi-Lac Qui Parle-Le Sueur-Martin-
     McLeod-Meeker-Nicollet-Pope-Ramsey-Redwood-Renville-Rice-
     Scott-Sherburne-Sibley-Stearns-Steele-Stevens-Swift-
     Waseca-Washington-Watonwan-Wright-Yellow Medicine.
WI...Wind Advisory until 10 PM CDT this evening for Chippewa-Dunn-
     Eau Claire-Pepin-Pierce-St. Croix.

&&

$$

DISCUSSION...PV
AVIATION...Dye