Minnetonka, Minnesota 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

625
FXUS63 KMPX 232046
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
246 PM CST Mon Dec 23 2024

.KEY MESSAGES...

-  Areas of dense fog possible in western MN tonight/Tuesday
   morning. More widespread dense fog possible Tuesday
   night/Wednesday morning.

-  A warming trend will occur this week with highs in the low
   to mid 30s by Christmas and near 40 possible by later in the
   week.

-  Rain chances increase late week into this weekend.

&&

.DISCUSSION...
Issued at 239 PM CST Mon Dec 23 2024

A couple of isolated snow showers lingering near the MN/WI border
early this afternoon will continue moving south-southeast, exiting
our area within the next 2 hours. If one happens to get caught in a
shower, expect briefly reduced visibilities but little to no snow
accumulation. After this, we look to stay dry with mostly cloudy to
cloudy skies into at least Thursday as forecast models show a lack
of any meaningful disturbances affecting the Northern Plains/Upper
Midwest. Instead, the theme for the week will be steadily warming
temperatures as upper-level ridging slowly moves over the central
CONUS, allowing southerly/southwesterly low-level flow to occur
underneath. Guidance shows forecast highs reaching the low to mid
30s by Christmas Day and then upper 30s to lower 40s by Friday.
Meanwhile, tonight`s lows will still be chilly, with mid teens in
western and central MN, warming to low to mid 20s elsewhere.
However, overnight lows will also trend upward, potentially
exceeding the subfreezing mark area-wide Thursday night.

The main weather concern through Thursday will be the possibility of
dense fog/freezing fog during the overnight and morning hours. The
southerly low-level flow will cause sustained WAA and, to a degree,
moisture advection over the Northern Plains/Upper Midwest. With our
current snowpack, surface temperatures will struggle to warm as fast
as aloft, creating a strong temperature inversion. A near
saturated boundary layer will occur, with only additional
moistening likely as snow melts when temperatures exceed the
freezing mark. The result will be the development of fog. This
is already starting to occur in western MN this afternoon where
visibilities have been reduced to 3-5sm. Fog in this region is
expected to continue to worsen through tonight and a Dense Fog
Advisory may be necessary in future forecasts. With
temperatures well below freezing, the chances of this fog being
freezing fog is high, which can cause slick roads due to icing
of surfaces. This could make the morning commute hazardous.
Forecast soundings only show the dense fog becoming more
widespread Tuesday night into Wednesday morning.

Our next chance of precipitation looks to be Friday through Saturday
as forecast models show a disorganized shortwave passing northeast
from the Central Plains to the Midwest. This current shortwave track
would place us in the precipitation shield to the north of the
surface low. As mentioned prior, temperatures by late week/this
weekend will be warm, such that rain will be the most likely
precipitation type during the day. Snow would become more possible
at night as temperatures cool to near freezing, particularly across
western MN and when the system exits. Ensemble QPF amounts only
favor about a 0.5" for the Twin Cities, but this could put a
good dent into our already dwindling snowpack. Long-range
guidance does show the pattern changing again by early next
week, as a strong, zonal upper-level jet crosses the Rockies.
EPS and GEFS both forecast cold 850 hPa temperature anomalies
following the jet into the Northern and Central Plains during
the first half of next week. Thus, our forecast warm spell
doesn`t appear to be too prolonged at this time.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1133 AM CST Mon Dec 23 2024

Some light drizzle/mist has been ongoing this morning with lower
cigs moving in from the north. This trend is expected to
continue with mainly MVFR/IFR conditions through early evening
before IFR/LIFR takes over. North-northwesterly winds will go
calm overnight, which will only help the fog chances. Very
little if any improvement in cigs are expected by the end of the
period. Winds will become southerly but remain under 5kts.

KMSP...After a few snow showers earlier in the day, the
remainder of the period should be dry aside from some mist/fog.
IFR cigs/vis settle in after 06z and are expected to improve
back to low end MVFR by late tomorrow morning/early afternoon.

/OUTLOOK FOR KMSP/
WED...MVFR, chc IFR. Wind SE 5-10kts.
THU...MVFR/IFR. Wind S 5-10kts.
FRI...MVFR/IFR, chc -SHRA. Wind SE 5-10kts.

&&

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

&&

$$

DISCUSSION...CTG
AVIATION...Dye