NWS Forecast Discussion

FXUS63 KMPX 092353

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
553 PM CST Sun Dec 9 2018

.SHORT TERM...(This evening through Monday)
Issued at 252 PM CST Sun Dec 9 2018

Clear skies, light winds, and temperatures nearing 30 have made for
a pleasant day by early December standards. The clear skies will
continue into the evening hours, but models are strongly indicating
the development of stratus and fog from Iowa northeastward across
southeastern Minnesota into western and northern Wisconsin. SREF and
HREF probs for stratus occurrence are non-zero this afternoon for
these areas, so it could be the models are a little too eager to
develop this stuff, at least early in the period. It also isn`t
entirely clear what would be supporting this, aside from cooling the
near surface layer after sunset. Continued the mention of fog and
partly/mostly cloudy skies from the previous forecast, but confined
it to southern/eastern MN into WI along the axis of high probs in
the guidance.

It would take some time to burn off the stratus Monday morning, if
it develops tonight. Highs Monday should be a couple degrees warmer
than today with low to mid 30s common across MN, except a bit cooler
than that further east.

.LONG TERM...(Monday night through Sunday)
Issued at 252 PM CST Sun Dec 9 2018

Prevalent westerly mid/upper flow will translate to mild
temperatures overall during the long term period, along with the
potential for multiple quick bouts of light precipitation.

The first of these waves moves across the central CONUS on
Wednesday. The associated inverted surface trough passes to our
south, as does the best mid-level forcing. Therefore any precip
in our area will be fairly light at best, in the form of light
snow or even possibly light freezing drizzle as a few of the
models are indicating in Bufkit profiles. This could start as
early as the overnight hours into Wednesday morning, but for now
have kept the mention during the daytime on Wednesday.

The next wave speeds in already on Wednesday night into Thursday
morning. Thermal profiles look a tad colder with this one, so
primarily light snow is expected at this point. Moisture and
longevity/strength of forcing are all modest, so again any
accumulations would be minor at best.

Mid level ridging then looks to build in for the remainder of the
week, bringing dry weather and maintaining temperatures well into
the 30s for highs through the upcoming weekend.


.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 546 PM CST Sun Dec 9 2018 Fog and areas of low ceilings
are expected to develop again tonight through mid morning,
primarily across southern Minnesota and west-central Wisconsin.
The lowest visibilities are expected at RWF & MKT where LIFR
visibilities are possible, with low-end MVFR visibilities at
MSP/RNH/EAU. Conditions will improve by mid- morning with VFR
conditions expected through tomorrow afternoon. South-Southwest
winds tonight into tomorrow morning, increasing to 7-10 kts by the
end of the period.

KMSP...Lowest visibilities should remain south of the terminal,
but expect MVFR visibilities down to 3SM to develop early tomorrow
morning and last through mid-morning.

Wed...MVFR ceilings. Wind light and variable.
Thu...MVFR ceilings. Wind SW, becoming W at 5kts.
Fri...VFR. Wind SW 5kts.




NWS MPX Office Area Forecast Discussion

Script by Ken True @Saratoga-Weather.org