Area Forecast Discussion
Issued by NWS Twin Cities, MN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

FXUS63 KMPX 090507

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
1107 PM CST Thu Dec 8 2016

.SHORT TERM...(This evening through Friday)
Issued at 245 PM CST Thu Dec 8 2016

Very similar from last nights forecast with enough moisture in the
dendritic growth zone to continue scattered snow showers/flurries
through the evening for mainly the eastern half of MPX forecast
area. It could even continue for western Wisconsin on Friday as
cyclonic flow continues in the area along with the necessary
ingredient for dendrites to form. The continued cold air advection
tonight, and into Friday will lead for highs only rising into the

.LONG TERM...(Friday night through Thursday)
Issued at 245 PM CST Thu Dec 8 2016

The main concern for the longer term is the snow potential from
Saturday/Saturday night event and overall model evolution of the
trough amplification and timing of new arctic air invasion early
next week.

Initially dry conditions are expected Friday night ahead of the
next short wave. It appears the NAM is the odd model out once
again...with its farther north solution for the Saturday snow
event. Feel confident enough to drop heavier snow accumulations
mainly along and south of the MN River...which has been consistent
with most of the deterministic runs. Followed more of the GFS
solution for its evolution...which appeared to be a compromise
between the more amplified 12z NAM and the farther south 12z
ECMWF. This leaves a swath of snow in solid advisory range(3 to 5
inches accumulation) from near Morris-Willmar-Southwest Metro_and
southern Goodhue Co. with the higher amounts mainly over south
central MN close to I90. Looking at dendritic growth potential off
the GFS...shows better omega and thickness of the DGZ across southcentral
MN during the late morning Saturday lingering into Saturday
evening. We should see a decent burst of snow 2-3 inches across
that region of the state. Isentropic lift is strong(280K Sfc) over
the area with a solid 2 g/kg into south central MN through 12z Sun
along the MN/IA border. This could lead to a 6-7 inch total close
to the border through the period.

The system shifts east rapidly into Saturday night...and should
end through 12z Sun. Models are coming more in agreement with the
secondary short wave affecting the region later Sunday into
Monday. The GFS remains farther south with it snow
development...with the other deterministic runs favoring a more
northern track and more amplified wave, We will continue with
chance pops for this feature at this time and continue to monitor
model performance in later runs.

Following this feature the timing of the arctic boundary moves
into eastern MN by late Monday afternoon. We will continue to
trend a chance of light snow/snow showers with the passage of the
front through Monday night. The coldest day appears to be Tuesday
night/Wednesday with some potential of teens below zero over the
west ...if clouds clear and winds die off. We will drop readings
a degree or two for now. Below normal temperature trends should
continue through next week.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1100 PM CST Thu Dec 8 2016

Well, there has been a large area of clearing developing over the
last 2-3 hours and it looks to continue for at least the first
half of the night. That`s the biggest change to the forecast.
There is still more cloud cover behind this clearing that will
likely move in late tonight.


So far the ceilings are looking better than anticipated this
evening with the partial clearing and dwindling snow flurries. We
do expect another round of cloud cover (potential at or just below
1500ft) late tonight.

Sat...MVFR, then IFR in SN. SE wind 5-10 kts.
Sun...IFR/MVFR in SN early. MVFR/VFR possible late. N wind 5-10 kts.
Mon...MVFR/VFR with -sn possible. WNW wind 5-10 kts.




AVIATION...CLF is the U.S. government's official web portal to all federal, state and local government web resources and services.