Plymouth, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

039
FXUS63 KMPX 210844
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
244 AM CST Thu Nov 21 2024

.KEY MESSAGES...

- A slippery morning commute is expected with conditions on
  untreated roads likely to be similar to last night.

- A few areas of light rain or drizzle possible in central
  Minnesota and western Wisconsin this afternoon. Temperatures
  will be warm enough to keep it all liquid.

- Cooler temperatures through the middle of next week with highs
  falling into the upper 20s early next week.

&&

.DISCUSSION...
Issued at 243 AM CST Thu Nov 21 2024

The morning MPX radar loop continues to show very light returns
amidst the low level stratus, favoring the region south of the
metro as the showers try and wrap in towards the center of the
low pressure system over Lake Michigan. A few stations continue
to report light snow or unknown precipitation, which typically
means either a mist or freezing drizzle light enough to not be
recognized. What this means for us is the road conditions at the
end of the evening commute will continue through this morning`s
commute barring any overnight treatments being done, with a
slow and icy commute expected. Extra time should be taken to get
to any morning destinations, especially if the route includes
an elevated feature such as a bridge or overpass which tend to
hold onto ice better than roadways in contact with the ground.
The story for today will be continued gusty winds which will
blow some of the fresh snow around resulting in further travel
hazards in the form of reduced visibility, alongside a bit of
drizzle possible mainly in central Minnesota to western
Wisconsin wrapping around the system over the Great Lakes. High
temperatures will be colder in western Minnesota where the winds
will have been out of the north to northwest for longer, with
near 30 on the SD/ND/MN border compared to near 40 in the metro,
and low to mid 40s in western Wisconsin. This should keep any
of the wrap around light precipitation as pure liquid with any
kind of impacts from colder temperatures waiting until
temperatures fall again tomorrow night. These temperatures
should also alleviate the travel concerns after this morning,
such that dry conditions will return to most roadways by midday.


The pressure gradient associated with the low pressure system will
weaken by sunrise Friday as winds diminish with northerly flow aloft
as the upper level jet streak weakens as ridging builds over the
northern CONUS by Saturday. Conditions will remain dry through
Saturday with a small chance returning on Sunday as guidance remains
unconvinced of a single solution for right now. The stronger upper
level jet likely stays south of the region as another upper level
low slides eastwards across south-central Canada, with our chance
for precipitation mainly relying on a weak cold front sliding
through Sunday evening into Monday morning. Deterministic guidance
would wait until the system is closer to Michigan to produce light
precipitation, with ensemble guidance loosely following that trend
as a few members of each of the EPS/GEFS/CFS suggest some light
precipitation on Monday. The most likely outcome for now is a few
weak showers but overall mostly cloudy skies being the primary
result with the current setup, as we lack any sort of upper level
support unless the southern stream jet trends a bit farther
northwards or the Canadian system stalls and keeps the front more
developed west of where it currently wants to produce more showers.
This pattern doesn`t change by midweek with upper level flow
remaining fairly weak with the southern jet a full state away and no
strong surface systems to force any active weather. Temperatures
will trend cooler as a result of the front moving through Sunday
into Monday, with highs struggling to reach 30 across the region
early next week.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1049 PM CST Wed Nov 20 2024

Models have not done well with cigs/vis or wind this evening.
Winds are considerably lighter than guidance and ceilings are a
mix of higher or lower than guidance depending on the location.
Additionally, there are a handful of UP/BR reports, particularly
across western Minnesota. Suspect this is freezing drizzle that
should come to an end over the next 2-3 hours. Mainly MVFR cigs
are expected through the period. As mentioned in the previous
discussion, a few brief hours of VFR conditions are possible
through early this morning for our easternmost sites. Winds are
gusting in the 15-20kt range, but should come back up into the
25-30kt range for gusts by tomorrow morning through the late
afternoon.

KMSP...Very frustrating forecast as VFR conditions have
returned to start the TAF period. Kept VFR in there through 12z
based on satellite trends and upstream obs, but added a TEMPO
group for MVFR since I would not be surprised if it comes down
occasionally. MVFR should return after sunrise and stick around
through the end of the period. As mentioned above, winds will
increase by tomorrow morning into the 25-30kt range.

/OUTLOOK FOR KMSP/
FRI...Chc MVFR cigs. Wind NW 10-15kts.
SAT...Chc MVFR cigs. Wind NW 5-10 kts.
SUN...VFR. Wind SE 5-10 kts.

&&

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

&&

$$

DISCUSSION...TDH
AVIATION...Dye