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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
335 am CDT Monday Sep 15 2014

Short term...(today and tonight)
issued at 330 am CDT Monday Sep 15 2014

Water vapor imagery shows a decent shortwave trough poking into
Minnesota early this morning...while radar imagery shows rain
blossoming over southern Minnesota. Models have been a bit too
far south with their depiction of precipitation...per radar
trends. A couple of the hi-res models...namely the hopwrf and
hrrr...have done a respectable job picking up on the northern
extent of the precipitation. Have therefore leaned toward those
two models with respect to hourly probability of precipitation for today. While the area
of rain does sag slightly south-southeast with time...think
locations as far north as the Interstate 94 corridor have a decent
shot at least picking up a hundredth or two of did
adjust the 20-30 pop chances about 50 miles farther north. The
responsible shortwave and pv advection shift out of the area
pretty efficiently this do still expect the rain to
end for the afternoon...with clearing skies commencing
accordingly. With weak cold air advection in the wake of the
trough...will see below normal highs in the upper 50s to lower

The concern for tonight will then become the potential for skies clear and winds decrease/decouple. The most
susceptible area will be central/west central WI...where forecast
lows dip into the middle 30s. May eventually need a frost advisory for
areas up toward Rice Lake and Ladysmith if 12z runs support current
wind/sky cover/temperature expectations.

Long term...(tuesday through sunday)
issued at 330 am CDT Monday Sep 15 2014

Weather models continued to advertise dry conds through Thursday with
temperatures near or slightly blw seasonable norms. The mean upper flow
will slowly transition to more zonal by the end of the week...then
change again by late in the weekend as a strong upper ridge begins to
build over The Rockies.

In the short term...a weak backdoor front is expected to move
southward across the western Great Lakes by Wednesday. Only a wind
shift to the north/NE and slightly cooler temperatures will occur with this
front. Strong return flow will commence Thursday/Friday leading to
above normal temperatures as the surface pressure gradient strengthens along
the High Plains. The strengthening pressure gradient is due to
strong height falls as a storm system begins to move out of the
northern rockies. This will set the stage for strong moisture
advection along the front Friday. Latest cips have the
possibility of 80 degree temperatures in western Minnesota Friday afternoon...with
middle to upper 70s in the east. In addition...severe weather is possible
especially considering the strong jet interaction with the
moisture return.

As discussed last night...analog composites for the 6-10 and 8-14
day extended period remain favorable for a strong ridge building
across the High Plains...and possible into the upper Midwest the
week of sept 22nd. This is in response to strong height falls in
the Gulf of Alaska and anticipated northern movement of the upper
jet core. For now...will only advertise a warmup for the week of
sept 22nd...and not get to excited for these above normal temperatures to
last for more than a few days.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1155 PM CDT sun Sep 14 2014

Rain continues to struggle developing due to the amount of dry air
across the upper Midwest. Still think areas around and south/east
of rwf have a good shot at seeing rain overnight...but think it
will miss the other taf sites. VFR conditions through the period.

Kmsp...VFR conditions until further notice. Middle level clouds will
dissipate Monday afternoon with northwest winds slowly backing
southwest Monday night.

/Outlook for kmsp/
Tuesday...VFR. Winds SW at 10 kts.
Wednesday...VFR. Winds south-southeast at 5 kts.
Thursday...VFR. Winds southeast at 10 kts.


Mpx watches/warnings/advisories...


long term...jlt

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