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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
728 am CDT Monday Mar 30 2015

Short term...(today through tuesday)
issued at 503 am CDT Monday Mar 30 2015

It's a quiet weather morning across Minnesota and Wisconsin with
fairly mild temperatures and just a few passing high clouds. The
atmospheric wave that produced the rain and strong winds yesterday
is now driving showers and thunderstorm across the southeast U.S.
Upstream of the forecast area there is an enhanced region of middle-
level water vapor associated with a shortwave that will drop
southeast across the upper Mississippi River valley today and
tonight. The result will be a weak surface low that tracks across
the area late this morning and early afternoon. The frontogenesis
north of the surface wave isn't overly impressive ... it will
likely be enough to shake light rain north of the I-94 corridor. The
lower atmosphere is dry...and we dont expect much more than a few
hundredths of accumulation where it does rain. Most of Minnesota
will remain dry.

Long term...(tuesday through sunday)
issued at 500 am CDT Monday Mar 30 2015

A warm and breezy start to the week will be followed by cooler temperatures
for the end of the week as low amplitude northwest upper level flow
sets up across the region in the wake of the midweek cold front. If
convection develops along this front Wednesday afternoon/evening
could see some isolated reports of severe weather...but at this time
probably remains fairly low across MN/WI...with a higher
likelihood down around the I-80 corridor as opposed to I-90.

Models continue to show a shortwave moving across the international
border early this week...with theta_e advection spreading out ahead
of it across the upper Midwest. Forecast soundings show a warm layer
just above 800mb...with steep lapse rates in the elevated mixing
layer above it. If the surface winds ahead of the cold front take on
a more southwesterly opposed to southerly...than the
low level covergence will not be sufficient for breaking through the
cap. The same result will occur if low level moisture advection is
less than indicated. For now...continued with probability of precipitation Wednesday
afternoon/evening...centered around the southeastern portion of the
County Warning Area. The low level shear profile remains favorable for a wind threat
if convection does develop.

Looking ahead...cooler temperatures will settle across the upper Midwest in
the wake of this front. By the end of the work week temperatures
will be near or below the seasonal average for early April.

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1047 PM CDT sun Mar 29 2015

Light westerly winds overnight will back to the southeast early on
Monday as a wave of low pressure drops southeast across mm and WI
during the afternoon and evening. Added vcsh to krnh and Keau for
about a three hour period during the late morning/early afternoon
hours when a band of light rain may pass these sites. Still looks
VFR through the period at all sites. Winds will become west-northwest during
the afternoon across western Minnesota with speeds increasing to 10-15
knots with gusts from 20-25 knots. area of broken-ovc060-080 will pass across the airfield
overnight and Monday with scattered conditions developing by Monday
evening. Light west winds backing to the southeast Monday morning
and then returning more westerly by evening.

/Outlook for kmsp/
Tuesday...VFR. Winds northwest 5-10 kts.
Wednesday...VFR. MVFR/-shra possible in the aftn/eve. Winds S 20g35 kts.
Thursday...VFR. Winds west-northwest 25g40 kts.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 730 PM CDT Monday Mar 30 2015

Mainly a dry forecast /outside of possibly light rain at Keau
later on today/ with VFR conditions and passing high clouds. Look
for generally light SW winds...then light S-southeast winds...then
veering all the way to west-northwest with the passage of a cold front this
afternoon and evening.

the wind forecast is tricky today due to an advancing weak low
pressure system that will pass nearly right overhead. The result
will be winds that wobble around a little bit today /mainly S-SW/
before the cold front comes through this evening.

/Outlook for kmsp/
Tuesday...VFR. Winds northwest 5-10 kts.
Wednesday...VFR. MVFR/-shra possible in the aftn/eve. Winds S 20g35 kts.
Thursday...VFR. Winds west-northwest 25g40 kts.


Fire weather...
issued at 502 am CDT Monday Mar 30 2015

There is a fire weather threat in southwest Minnesota due to the
combination of afternoon relative humidity values near 25% and wind up near 30 miles per hour
for a few hours this afternoon. There will be only a light breeze
until the forecast area gets on the backside of the surface low.
Most of the model guidance today is too warm with the dewpoints and
thus too high with the humidity values. The rap and only 1 or 2
other short-range model guidance are low enough with the relative humidity
today...the European model (ecmwf)/NAM/GFS seem too high given the setup. This winds
will not be nearly as strong today as campared to yesterday.


Mpx watches/warnings/advisories... flag warning from noon today to 7 PM CDT this evening for



Short term...clf
long term...jrb
fire weather...clf

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