Forecast Discussion / NWS-Twin Cities

003
FXUS63 KMPX 262320
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
620 PM CDT Wed Mar 26 2025

.KEY MESSAGES...

- Another round of scattered showers across Minnesota late this
  afternoon and evening.

- Warming trend continues through Friday. Very warm and somewhat
  humid conditions south of a warm front with highs potentially
  in the mid 80s. Much colder temperatures just to the north.

- Widespread precipitation arrives this weekend. Rain will be
  the dominant p-type, but a transition to snow on Saturday with
  some accumulation.

&&

.DISCUSSION...
Issued at 241 PM CDT Wed Mar 26 2025

Today through Thursday night... An area of mid-level clouds will
continue to move eastward and bring an increased chance for rain
showers through afternoon and evening hours. Our impulse will exit
by Thursday morning with drier conditions moving in through Friday
morning. Thursday looks like a fairly pleasant day given the time of
year. High temperatures will be in the mid 50s to lower 60s with
mostly sunny skies. This set up may lead to over achiever on
temperatures due to mixing higher than forecast. This scenario would
likely lead to RH values in the 20 to 30 percent range but winds
remain below threshold values for any fire weather concerns.
Regardless, do not be surprised if we see temperatures creep into
the mid 60s across portions of Minnesota Thursday afternoon.

Friday & Friday night... A broad and loosely organized area of low
pressure will consolidate over SD Thursday night. This will place a
tight thermal gradient ahead of the low pressure. This gradient will
serve as a baroclinic zone for the system to strengthen and spawn
precipitation Friday PM into Saturday. This boundary will become
more west-east oriented and surface flow to it`s south becomes more
southerly across southern MN. A 50 kt LLJ will develop over the
Plains and nose up into northern IA Thursday night, which will bring
a surge of low level moisture into central/eastern MN & western WI.
Our attention turns to Friday, which could be the warmest day of the
year so far for some of us, as the front lifts north before stalling
across central MN, the Twin Cities, and western WI. This will allow
moisture & instability to pool along the boundary before convective
initiation n Friday evening. While this isn`t an environment that
would jump out to us in our traditional severe season, it`s fairly
impressive for late March. Forecast soundings for south-central MN
reflect an EML with lapse rates of 8-9 C/km. Shear will be adequate,
too. Instability won`t be particularly impressive but 500 to 1000+
J/kg appears realistic... and after collaboration with SPC we`ve
seen an extension of the Marginal Risk (1 out of 5) for day 3
(Friday). This highlights the potential for isolated thunderstorms
along & south of the boundary Friday PM.

Saturday through Sunday... Our initial surface low will wash out and
leave behind a stationary boundary that stretches across northern
Iowa and southern Wisconsin from southwest to northeast. This will
act as a focus point for the another more potent shortwave to
activate Saturday & Sunday. The stronger system will bring us the
chance for all precipitation types. Another slug of Pacific moisture
will move overhead and as our shortwave races towards the Great
Lakes region and sends a secondary surface low pressure northward
reinforcing the low level moisture. Precipitation will bloom along
the baroclinic zone with rain chances ramping up during the day
Saturday. A wintry mix will be likely across central Minnesota
before changing over to a sleet/snow mix and eventually all snow by
Saturday night. Guidance has come together with the threat of wintry
wx, but global guidance is in disagreement with timing of p-type
transition, placement of the band of snow, and track of the
secondary low pressure. Each variable adds exponential difficulty to
the equation of accumulating snow in Late March. However, the chance
for accumulating snow appears far greater than it did a day ago for
portions of western & central Minnesota for Saturday PM into Sunday
morning.

Cooler and drier air will follow early next week with largely
tranquil weather expected until the next system to watch develops in
the central U.S. midweek. This system could be yet another event
with rain, snow, and everything in-between. One things for sure - it
would have been nice to see this weather pattern in January.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 620 PM CDT Wed Mar 26 2025

VFR with winds becoming light overnight. This evening will see
some showers continue to track across Minnesota and into
Wisconsin. Low level dry air is making most of this rain
evaporate before reaching the surface, so have only kept VFR
PROB30 for SHRA in the TAFs. Tomorrow winds pick up from the
east around 10 knots.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/
FRI...VFR, chc MVFR/-RA late. Wind SE bcmg N 10-15 kts.
SAT...MVFR/RA, chc IFR. Wind NE 10-15G25 kts.
SUN...MVFR/RASN bcmg -SN, chc IFR. Wind NE 10-15G25 kts.

&&

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

&&

$$

DISCUSSION...BPH
AVIATION...NDC

NWS MPX Office Area Forecast Discussion