105
FXUS63 KMPX 140605
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
105 AM CDT Sat Sep 14 2024

.KEY MESSAGES...

- Scattered showers Saturday morning through the afternoon for
  eastern MN and western WI.

- Well above normal temperatures remain through at least next
  weekend, with a more active pattern for the second half of
  next week.

&&

.DISCUSSION...
Issued at 143 PM CDT Fri Sep 13 2024

It`s another beautiful September day with temperatures again heading
for the 80s (about 10 degrees above normal). There are however three
features on water vapor imagery and an h5 analysis that will be
impacting us through the weekend. One is the blocking high centered
over the Great Lakes, next are the remnants of Francine, which have
slammed on the breaks near the MO Bootheel as it encounters the
Great Lakes block, and three is a frontal boundary over the Dakotas.
Through this weekend, the blocking high will remain anchored from
the Great Lakes over to New England. This blocking high will cause
the remnants of Francine to slowly rain themselves out near its
currently location this afternoon, with the Dakotas front washing
out near the MN border tonight is the main upper support for the
front goes around the blocking high up to northwest Hudson Bay.
Although the primary remains of Francine will remain well southeast
of the MPX area, a shortwave and associated spoke of tropical
moisture has broken off from the main circulation and will track
from its current location over northern MO and be in the St. Croix
valley come Saturday morning. There continues to be a good deal of
spread with how far west this activity will make it, hence the PoPs
that max out at 50% from early Saturday morning through the
afternoon from eastern MN across western WI. Coverage looks
scattered and amounts fairly light, though an isolated rainfall total
between a half and one inch will be possible. This activity will
settle down Saturday night. Sunday, a spoke of drier will move into
MN from the west, but enough moisture will be lingering from
southeast MN up through western WI Sunday afternoon to drive an
isolated shower threat there.

Next week, model spread remains fairly large on when/where we`ll see
precipitation. A blocking high over eastern NOAM will remain a
dominate feature, with the big question being where does the plume
of deeper moisture and repeated rounds of rain end up. In the
deterministic models and ensembles, we see the zone for seeing
repeated rounds of rain setting up anywhere from MN over to the
central Dakotas. Given the blocking high to the east, we will not be
able to push any fronts through our region and with PWATs slowly
increasing to over 1.8" by the end of the week (over 200% of
normal), we will have a favorable setup for seeing repeated rounds
of heavy rainfall. At this point, it`s just a question of where
those individual waves heading around the blocking high end up,
which is why the NBM continues to advertise a long period of chance
PoPs from Wednesday through the rest of next work week. Within this
prolonged period of chance PoPs, there is a larger region of likely
PoPs Wednesday night. Upper flow will be pretty weak and given the
high PWATs, soundings are pretty moist (so limited lapse rates),
both of which really limit any potential for a more pronounced
severe risk. We will also see very little airmass change next week,
with daily highs in the low to mid 80s and lows in the low to mid
60s, temperatures that will be consistently running 10 to 15 degrees
above normal. And for those wondering when we may see some fall
temperatures, the EPS shows mild airmasses staying with us through
the rest of September, so it looks like our extended summer will be
continuing until further notice.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 102 AM CDT Sat Sep 14 2024

Aviation...VFR becoming MVFR with showers possible this morning.
Continuing to monitor a narrow band of -SHRA which is now nearing
AXN. So far, precip does not look to be reaching the ground so was
hesitant to mention precip for our western sites for now. Will
amend should things change. So far, confidence is strongest
over our eastern sites seeing potential -SHRA after 15z this
morning. Cigs will improve late this afternoon back to low VFR
mainly after 22z. Winds will remain southerly and increase
between 5-15kts by this afternoon.

KMSP...VFR overall with a chance for MVFR showers in the late
morning specifically between 15-18z. Some guidance does hint at
rain showers these expected rain showers holding off in the
morning which would increase the potential for isolated storms
over MSP in the early afternoon. Winds will remained sustained
out of the south between 10-15kts this period.

/OUTLOOK FOR KMSP/
SUN...VFR. Wind S 5-10 kts.
MON...VFR. S Chc MVFR/SHRA. Wind S 10-15 kts.
TUE...VFR. Wind SSE 10-15G20 kts.

&&

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

&&

$$

DISCUSSION...MPG
AVIATION...Dunleavy