Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
442 am CDT Sat Oct 10 2015
Short term...(today and tonight)
issued at 400 am CDT Sat Oct 10 2015
Early this morning...high pressure continues to work southeast of
the area...with southwesterly winds already increasing across
Minnesota and western Wisconsin as the surface pressure gradient
tightens. This begins a period of impressive warm air advection
through tomorrow...with the peak coming on Sunday. Passing high
clouds are expected today...otherwise a dry and clear forecast.
With the low levels warming rapidly and mixing to about 900mb
today...expect high temperatures top out in the low 80s across far
western Minnesota...middle 70s across eastern Minnesota...and upper 60s across
With the gradient continuing to tighten...southwest winds of 15 to
25 miles per hour with gusts around 30 miles per hour are likely today. For
tonight...skies will again be partly cloudy and southwest winds of 5
to 15 miles per hour are expected. With the much warmer air mass still
advancing into our area from the west...low temperatures will bottom out in
the 50s...relatively warm for this time of year.
Long term...(sunday through friday)
issued at 400 am CDT Sat Oct 10 2015
Very dry extended portion of the forecast will be highlighted by a
very warm and windy Sunday followed by strong cooling starting
Monday which will last through the rest of the week.
A warm front NE of the weather forecast office mpx County warning forecast area with a cold front lumbering through the
Dakotas on sun with a ridge axis aloft containing anomalously high
500 mb heights will produce near record high temperatures across the County warning forecast area. 850 mb
temperatures up to 25 degree c on sun over western/southern Minnesota with deep mixing will
produce highs well into the upper 80s for southwestern Minnesota while the
remainder of the the County warning forecast area will range from the upper 70s to the middle
80s. Values this high are not only nearly 25 degree f above
climatological norms but also very close to record highs in the
middle 80s at several sites.
The aforementioned cold front will then swing through Sun night into early
Monday. Very limited moisture will be associated with this system so
other than an increases in cloud cover...precipitation is widely not
expected with this frontal passage. However...what will be expected is a
significant increases in wind speeds due to a very tight pressure gradient
along with vorticity packing in vicinity of the frontal passage. This will translate
to enough mixing to tap 40-50kt winds down to the surface...making for
sustained 20-30mph winds with gusts around 45 miles per hour and likely the
need for wind headlines for Monday. With this strong increases in
winds will be a very noticeable drop in temperatures as pronounced cold air advection
with the frontal passage will make for a 20-25 degree drop in maximum temperatures across
the County warning forecast area starting on Monday.
Very little pattern change will then be the rule through the rest of
the week as temperatures will generally remain the same or drop slightly
as the week progresses with continued dry and precipitation-free conds.
Aviation...(for the 12z tafs through 12z Saturday night) issued
at 454 am CDT Sat Oct 10 2015
Very quiet period with just passing high clouds through the
forecast period. Surface wind is the primary weather concern.
Expect winds today to become southwesterly and increase markedly
through the morning...peaking in the afternoon with sustained
speeds of 15-20kts and gusts of 25 to 30kts possible. These will
fall back to around 10kts near sunset...then further decrease
Kmsp...no change from main discussion...breezy day and VFR with
high clouds moving through.
/Outlook for kmsp/
sun...VFR. Winds SW 10-15 kts.
Monday...VFR. MVFR ceilings possible. Winds northwest 20-25g35 kts.
Tuesday...VFR. Winds SW 5-10 kts.