NWS Forecast Discussion

FXUS63 KMPX 240840

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
340 AM CDT Sun Sep 24 2023

.DISCUSSION...(Today through Saturday)
Issued at 338 AM CDT Sun Sep 24 2023


- Scattered showers and storms possible this afternoon through
  Monday night.

- Dry weather will return by mid-week with above normal temperatures
  through next weekend.

Split flow aloft across NOAM this morning as the main jet is
displaced off to the north. There is an upper low to our west that
will dominate our short term pattern as it`s progression stalls
overhead. The pattern is not exactly a rex block, but the impacts
will be very similar as the flow slows down significantly over the
next few days. At the surface an expansive high pressure is centered
over Hudson Bay and Ontario that will become an important player
later on in the forecast period. Our surface low is sitting over the
ND/SD/MN border with it`s occluded front working through eastern MN
into western WI. There is scattered showers with an occasional
rumble of thunder mixed in here and there. We`ve managed to dodge a
bullet as yesterday`s severe potential was not realized, partially
due to the southern convection that tracked from Nebraska through
Iowa, and partially due to a bit of missed timing among interacting
features. What did play out is an area of locally heavy rainfall
across portions of south central and eastern MN. Our office in
Chanhassen ended up with a 24 hr total of 2.60", most of which fell
between 00z and 06z. This "bullseye" ended up further east than
guidance suggested last night, which was a concern due to the
convective nature of the precipitation. Looking ahead, the ULL will
provide a few additional chances of showers over the next few days.

Drier air works in behind the occluded front and should allow us to
stay dry for most of the day. Higher PoPs return across west central
MN this afternoon as moisture wraps around the ULL. If you have
outdoor plans it could be helpful to check the radar before you head
out the door, but it will  not be an all day rain event. Highs reach
into the upper 60s and 70s with little to no sunshine to help warm
us further. Tonight will cool back into the 50s for most locations
and scattered showers continue to pivot around the ULL. Showers and
thunderstorms will be possible through Tuesday AM across nearly our
entire forecast area as continual lift will cause showers and storms
to develop and wrap around the ULL. Thunderstorms will be most
likely during the afternoon hours with no severe weather expected.
Guidance shows that an additional 1" + of much needed rain could
occur through Tuesday morning across portions of central MN into
western WI. Rain chances finally taper off Tuesday as the ULL
gradually drifts ESEward and exits the region. It`s important to
note that guidance struggles to resolve cut off/closed lows in a
blocking pattern so precip chances may lag further into the forecast
period. Highs will be in the 60s and lower 70s Sunday thru Tuesday
with lows in the 50s and lower 60s.

Afterwards, the pattern turns drier with temperatures forecast to
warm above normal for the end of week. Long range guidance favors a
trough to dig into the western CONUS during the latter half of the
week and amplify the pattern with a ridge building in over the Great
Lakes and into eastern Canada. High temperatures in the upper 70s
with a good chance for highs to hit 80 again next Friday and
Saturday. NBM PoPs begin to creep up heading into next weekend but
I`d expect the overall pattern to slow and those chances to be
further delayed.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1200 AM CDT Sun Sep 24 2023

Thunder chances have diminished over the last hour or two. Scattered
showers will continue through the night with steadier SHRA over the
eastern sites (KMSP/KRNH/KEAU). MVFR cigs will trend toward IFR
conditions tonight, but improvement back to MVFR and eventually VFR
is expected later today. SE winds 10-15kts with gusts up to 25kts
will gradually decreased through the morning.

KMSP... Scattered showers continue tonight before diminishing later
this morning. There is still some uncertainty to the additional SHRA
chances today. We`ve added a prob30 to address the chance in the
21-24z time window, but guidance suggests that it could trend a bit

Mon...Chc MVFR/-SHRA/-TSRA. Wind S 10 kts.
Tue...VFR. Wind E 10 kts.
Wed...VFR. Wind SE 10 kts.





NWS MPX Office Area Forecast Discussion

Script by Ken True @Saratoga-Weather.org