Plymouth, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

123
FXUS63 KMPX 140457
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1057 PM CST Wed Nov 13 2024

.KEY MESSAGES...

- Light rain will decrease in coverage with eastward movement
  this evening. Areas of patchy fog/mist linger into Thursday
  morning.

- Drying out for the remainder of the work week. Temperatures warm
  well into the 50s this weekend.

- Unsettled, very active upper-level pattern to bring the return
  of precipitation chances across the Upper Midwest by the
  middle of next week.

&&

.UPDATE...
Issued at 601 PM CST Wed Nov 13 2024

Light precip was continuing across the region, so did increase
pops a bit and used drizzle wording as the weather type. Winds
were light across the region as well. The precip should
dissipate this evening and overnight as subsidence from upper
level height rises moves across the region. This will set the
stage for light winds to continue, and this time of year that
means clouds will stick around as well given the low sun angle
of mid-November.
Looking ahead, confidence continues to grow in a large system
bringing widespread rain (possibly snow) across the region late
Monday into the middle of next week, but details on the storm
track timing and placement remain uncertain.

&&

.DISCUSSION...
Issued at 137 PM CST Wed Nov 13 2024

It`s been a tale of two different weather stories across the region
thus far today, with widespread rain across western Minnesota and
drier conditions across eastern Minnesota and western Wisconsin.
An initial band of rain developed on the nose of the nocturnal
low-level jet, in the exit region of a shortwave trough. Latest
KMPX radar imagery illustrates that the prolonged south to
north motion of rainfall has started to shift east, which is a
trend that will continue through this evening. Coverage and
intensity of rainfall will gradually wane with eastern extent,
given the departure of favorable moisture transport and
sufficient lift. However, forecast soundings indicate that low-
level moisture will linger across eastern Minnesota and western
Wisconsin. Essentially this means less in the way of steady
precipitation and more in the way of mist/patchy fog through
the evening.

Forecast soundings have trended in a pessimistic direction with
regards to sky cover tomorrow. It looks like low stratus and some
patchy fog will linger through at least mid-morning, with little
hope for breaks in the clouds. Thursday morning lows in the upper
30s are expected to only warm about 10 degrees or so into the upper
40s for highs tomorrow afternoon. Uncertainty exists with respect to
sky cover on Friday, as there are two scenarios currently in play:
Skies clear by early Friday morning, allowing for the development of
fog. Scenario two features a slower improvement to the skies, with
low stratus lingering into the daytime hours. This would limit the
potential for dense fog to develop. Latest RAP soundings have
trended in the direction of keeping the stratus around through mid-
morning Friday. Despite the challenges in the sky cover forecast, we
do have high confidence in dry weather for the end of the work week
and through the weekend.

Upper-level ridging will build across the Upper Midwest to open the
weekend, with mid-level flow/warm advection set to increase out of
the southwest. Southerly surface winds will increase by Saturday,
which will bring improvements to the sky cover and warmer
temperatures. We`ve opted to trend highs towards the NBM 90th
percentile (mid to upper 50s) given the favorable WAA regime.
Surface low pressure is progged to slide northeast out of the
Dakotas towards southern Canada Saturday into Sunday. A frontal
passage associated with the surface low is not expected to produce
much in the way of precipitation chances, however winds will kick
out of the west on Sunday. Slightly cooler, but still seasonal highs
in the upper 40s/low 50s will follow as a result.

Rain chances will return to the region early next week, as a vigorous
cutoff low pivots northeast through the central CONUS and rides
the southwesterly flow into the Upper Midwest. We currently
have medium to high confidence that widespread rain will accompany
this feature beginning Monday evening, which is reflected by
40-50% PoPs in the current forecast. Uncertainty increases
substantially beyond midday Tuesday, as there are currently a
multitude of solutions concerning the occlusion of the cutoff
and resultant phase with an upstream trough set to dig in over
the central CONUS Wednesday. Models typically struggle with the
phasing of large scale features at this distance, so it`s no
surprise that forecast guidance varies significantly from run to
run/model to model. This is amplified by the amount of moving
pieces in the upper air pattern spanning from the Pacific
Northwest to the tropics/SE CONUS next week. Where, when, and
how strong phasing of the upper air features and eventual
occlusion of the surface system will make a big difference in
the weather experienced locally. Fans of winter weather may be
quick to latch onto a solution that produces bullish snowfall
amounts across the region during the second half of next week.
It`s simply too soon to have confidence in any one outcome. For
now, get ready to enjoy a nice November weekend by MSP standards
and stay tuned for more information regarding active weather
next week. What seems more certain at this time is the arrival
of colder air by the end of next week. (It`s about time!)

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1052 PM CST Wed Nov 13 2024

Satellite shows what is set to be our situation for the first
12-18 hours of the TAF period, being stratus/low clouds/fog for
all Minnesota sites with a small amount of clearing assisted by
higher level clouds over MSP/RNH/EAU. IFR/LIFR CIGS/VIS are
expected with the fog especially in western MN for AXN/RWF, with
slightly high CIGS/VIS as you head east resulting in an MVFR/IFR
mix. Winds will remain light under 3-4kts favoring 200-220 but
remaining variable at times, including periods of calm surface
winds. Conditions should begin to improve later in the period,
with most sites returning to high MVFR/low VFR by the end of the
period as we dry out and clouds begin to disperse.

KMSP...The main question is how thick the fog gets overnight.
Right now the TAF caps VIS at 4-5sm with IFR/MVFR CIGS, but a
close eye needs to be kept on the trajectory and spread of
clearing and higher level clouds overnight.

/OUTLOOK FOR KMSP/
FRI...VFR. Wind SE 5-10kts.
SAT...VFR. Wind SE 15G25-30kts.
SUN...VFR. Wind W 10-15G25kts.

&&

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

&&

$$

UPDATE...JRB
DISCUSSION...Strus
AVIATION...TDH