NWS Forecast Discussion

Below is the latest Area Forecast Discussion from the Twin Cities National Weather Service office in Chanhassen, MN. It gives insight into why the forecasters are making the predictions you read in your local forecast. The overall "big picture" of the atmospheric setup is well described, as well as the forecasters' interpretation of the various Computer Atmospheric Models (CAMs). Sometimes, very specific information is available here that is not available, or otherwise generalized, in the public forecast.

523
FXUS63 KMPX 251103
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
603 AM CDT Fri Apr 25 2025

.KEY MESSAGES...

- Rain showers continue to move east and will exit west central
  Wisconsin by mid-morning (sooner in Minnesota), leading to a
  mostly dry and mild day.

- Next round of showers and storms will arrive Sunday into early
  next week with increasing chances for severe thunderstorms on
  Monday afternoon. Some stronger storms are also possible
  Sunday night.

&&

.DISCUSSION...
Issued at 130 AM CDT Fri Apr 25 2025

Showers continue across south-eastern Minnesota at present, but
continue to shift northeastward. A smaller area of rain has
moved into western Minnesota from South Dakota, but that is
anticipated to fall apart within the next few hours. Any
additional QPF from the west MN rain will be limited to a few
hundredths at best. Areas in western Wisconsin and SE MN can
expect to see a few tenths before all is said and done by late
morning. Taking a look at where things stand with respect to
what is typical by late April, with 5.42" liquid precip since
January 1st, MSP is only behind normal accumulated
precipitation by 0.28". With this latest event, Eau Claire is
actually slightly above and St.Cloud is only slightly below.
While year-to-date accumulated precipitation is on track so
far, we are entering the time of year where normal increases by
about a tenth a day. So any stretch of dry weather will quickly
create a deficit. Fortunately for the Upper Midwest, we don`t
look to have a stretch of dry weather in the near future!

As high pressure approaches, conditions will dry out and clouds
will gradually decrease from west to east with clear skies
taking hold by tonight. While the clear skies will allow
temperatures to drop into the upper 30s, the reward will be
grand on Saturday with upwards of 12 hours of sun and highs in
the mid 60s. Additionally, winds will be at bay for most (except
far western Minnesota where gusts in the upper teens are
possible), creating a practically perfect forecast for the last
Saturday of April.

Sunday through Tuesday brings our next period of active weather.
Sunday won`t be the main event, but shower and storm chances are
present nonetheless as southerly winds advect warm air and
moisture into the region. Anticipated precipitation from
scattered showers on Sunday will be minimal (less than 0.10"),
aside from areas that may get convection. Late Sunday into
Monday, a potent low pressure system will be entering the Upper
Midwest. The arrival of the surface front could bring some
stronger storms Sunday night into Monday. Despite early chances
for storms, strong WAA ahead of the upper level trough will
send Monday`s temperatures soaring into the upper 70s for most
and low 80s for those in SW MN. This will re-energize the
atmosphere for what continues to look like strong to severe
storms Monday afternoon and evening. At this distance from the
event (4+ days), SPC updates the severe outlook once a day and
that should happen in the next few hours. This being said, it is
fairly safe to say the 15-30% risk mentioned in the previous
discussion will prevail as guidance continues to show ample
surface-based CAPE, 40+ kts shear, with high dewpoints in the
60s. Looking at the ECMWF`s Extreme Forecast Index (EFI), both
forecast CAPE and temps for Monday have EFI values near/above
0.8 (80%). This generally signifies an unusual event based on
our area`s M-Climate. The M-Climate is a set of medium range re-
forecasts made up from the same calendar dates over the last 20
years, among other things. The Shift of Tails is 0, meaning very
few ensemble members are forecasting an extreme event. The take
home point? Unusually high CAPE values and maximum temps can be
forecast with higher confidence, but extremes are unlikely. CIN
will be something to keep an eye on, but the GEFS and GEPS are
forecasting relatively breakable values (-30 to -50 J/kg). All
severe threats remain possible with this setup. The finer
details will become more clear as Hi-Res models are available
later this weekend, but expect a rumble-y day on Monday.

Things will clear Monday night as high pressure returns for a
few days. Winds will shift to the NW early Tuesday, reigning the
highs back down to the upper 50s and low 60s on Tuesday. Warmer
temperatures in the 60s will return Wednesday through Friday,
with another chance for scattered rain showers Wednesday night
through Thursday as a weak low pressure center passes to the
north.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 603 AM CDT Fri Apr 25 2025

Light rain continues along and east of a line from RWF to STC.
The back edge will continue moving east this morning with
improving conditions thereafter. IFR conditions across southern
MN and parts of western WI will persist for much of the morning.
Cigs will rise and scatter our this afternoon.

KMSP...MSP is just north of the IFR conditions. There may be
brief instances of such cigs, otherwise MVFR is expected through
early afternoon. Occasional light rain will continue through
mid morning.

/OUTLOOK FOR KMSP/
SAT...VFR. Wind SE 5-10kts.
SUN...VFR, Chc -SHRA/MVFR. Wind SE 10-15kts.
MON...VFR, Chc -TSRA/MVFR. Wind S 10-15G25kts.

&&

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

&&

$$

DISCUSSION...PV
AVIATION...Borghoff

NWS MPX Office Area Forecast Discussion