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fxus63 kmpx 141816 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
116 PM CDT Mon Oct 14 2019

issued at 115 PM CDT Mon Oct 14 2019

Updated for 18z aviation discussion below.


Short term...(today through tuesday)
issued at 311 am CDT Mon Oct 14 2019

Early this morning, residual wrap around moisture continues to
affect parts of Minnesota and Wisconsin from the departing storm
system that brought over 2 feet of snow to North Dakota over the
weekend. Once this system moves off to the northeast, another
potent, but small/compact system will begin to affect the upper
Midwest late this evening. Moisture from the Gulf will rapidly
move northward ahead of this system moving into the northern
plains today. Moisture advection will increase significantly this
evening with showers developing along the nose of the low level
jet across southern Minnesota. Models have also been consistent
and even the cams suggest that a band of showers will develop
around midnight from St. Cloud, southeast toward the Twin Cities
and Rochester. There is even some elevated instability that
suggest a few rumbles of thunder. Once the precipitation starts,
it will quickly expand north/northeast across west central
Wisconsin, and into central Minnesota toward Tuesday morning.

A surface low is expected to develop across southern Minnesota
Tuesday morning and deepen rapidly as it moves into western
Wisconsin by the afternoon. The bulk of the steadier showers will
occur in central Minnesota and northern Wisconsin Tuesday morning
and afternoon. Once the surface low moves off to the east,
moisture will wrap southeast across eastern Minnesota. Atmospheric
soundings also indicate a rapid temperature drop in the saturated
layer below 5.0 kft in Central/Northeast Minnesota. This would
suggest that a mixture of rain/snow would develop as the
precipitation expands northward into central Minnesota/northern
Wisconsin. Therefore, I wouldn't be surprised to see a quick one
to two inches of snow from Brainerd to Duluth by late Tuesday
morning. Farther to the south, only a mixture of rain/snow is
expected and most of the precipitation should quickly depart the
area by the mid/late afternoon.

Long term...(tuesday night through sunday)
issued at 311 am CDT Mon Oct 14 2019

The long term period looks pretty quiet, until we get to the end of
it at the end of next weekend into the following week. We'll
continue to run below normal on temperatures Wednesday and Thursday,
but by the end of the week, a trough digging into The Rockies will
help send our temperatures back a little above normal for Friday
into the weekend, when we should see some fairly widespread highs
into the 60s. Confidence in the forecast is pretty high through
Saturday, but after that, spread in the deterministic models and
ensembles becomes quite large, with confidence in the forecast
decreasing significantly.

We'll start the long term Wednesday with your typical Post system
cool and cloudy fall day, with temperatures only expected to top out
in the 40s. However, by Thursday, we'll see strong southerly flow
develop in response to falling heights across The Rockies. The first
bit of energy from this western trough is still progged to come
across the region Friday night. We will warm considerably out ahead
of this wave, with highs into the 60s looking like a good bet for
all but the northern reaches of the mpx County Warning Area on Friday, with the nbm
possibly running a few degrees too cold given h85 temps progged to
be up around 12c on Friday. Moisture still looks lacking along the
front, but moisture from the south eventually meets up with the
front Friday night, but not until it's almost east of our area, with
models continuing to favor precip Friday night maybe beginning in
western WI, with it east of our area by Saturday. High pressure
coming in behind this front will be coming from the central rockies,
so it will still be a mild airmass behind it, with another day of
highs in the 60s looking likely for Saturday.

After Saturday, things diverge quite a bit, but the one thing all of
the models and ensemble means show is that on Sunday, the trough
will dig into the Southern Plains, with a major extratropical
cyclone impacting the central Continental U.S. Sunday into the start of the
next work week. The main differences we are seeing at this point
deals with the degree of phasing seen with the southern extent of
the trough and the northern stream. The European model (ecmwf) continues to keep this
system phased and is by far the strongest with a powerful low
working across the upper MS valley on Monday. The Canadian and GFS
have less phasing of the southern system with the northern stream
and have a weaker low that slides off to our southeast. For both
scenarios, this system is not working with as much cold air as the
system we saw last week, so at this time, we probably are not
looking at a significant snow maker, it's either a cold light rain
(gfs) or thunderstorms and heavier rain topped off with some snow at
the end (ecmwf). Given the spread seen in the models, there was no
reason to fight what the nbm gave US for Sunday/Monday.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 115 PM CDT Mon Oct 14 2019

VFR through this evening, with few/sct cu developing across
eastern Minnesota and western Wisconsin. Showers are still
expected to develop after midnight over central/eastern
Minnesota and spread northeast, with widespread showers
continuing through the morning across central Minnesota and into
west- central Wisconsin. Can't rule out an isolated rumble or two
across eastern Minnesota and western Wisconsin, but probabilities
appear too low to include a mention of thunder. Ceilings are
expected to drop to MVFR area- wide overnight, and may approach
IFR by tomorrow morning. Southeast winds this afternoon back to
easterly overnight, and then become northwesterly tomorrow morning
behind a cold front. Gusts of 20-25 kts are expected to develop
behind the front.

Kmsp...showers are expected to develop over central and eastern
Minnesota after midnight, with -shra looking possible at the
terminal from 06-09z. A chance for scattered showers will
continue through the period, but the best chances look north and
east of the terminal. Expect ceilings to lower with the rain and
become MVFR by 09z and quickly degrade to around 015, remaining
low-end MVFR through the period.

/Outlook for kmsp/
Tue night... MVFR. Wind northwest 10-15 kts
Wed...MVFR bcmg VFR. Wind northwest 5-10 kts.
Thu...VFR. Wind south-southeast 5-10 kts.

Mpx watches/warnings/advisories...


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