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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
607 PM CST Thursday Mar 5 2015

Short term...(this evening through friday)
issued at 402 PM CST Thursday Mar 5 2015

Tonight-Friday...surface analysis shows the center of a 1040mb high over
the Iowa/MO border with pronounced northwest flow aloft. Further west over the
western Dakotas into the Central Plains...a snaking warm front will
gradually push ewrd...on the heels of the departing high pressure
area...through tomorrow afternoon. This shift will allow a more
pronounced southerly wind component tonight into tomorrow. In
addition...a weak middle level trough disturbance aloft will pass over
the region overnight. With a continued dry boundary layer...and
meager deep moisture and lift...this trough will produce nothing
more than an increase in clouds overnight through daybreak. Once this
trough moves through...northwest flow aloft will resume but with a more
Pacific component rather than Arctic. In addition...surface flow will
remain west to SW through the day tmrw. Thus...partial clearing is
expected with enhanced warm air advection tonight through tomorrow as the warm front
is expected to enter Minnesota. This combination of events will spell
rising temperatures overnight followed by highs on Friday that will be about
20 degrees warmer than today.

Long term...(friday night through thursday)
issued at 402 PM CST Thursday Mar 5 2015

Main change we have seen in the extended is some better agreement
between the GFS/European model (ecmwf) for the second half of next week...with the
GFS trending more toward the European model (ecmwf) /as opposed to the other way
around/. Otherwise...the rest of the forecast still looks
similar...with a couple of minor precipitation chances over the weekend
followed by highs 10 to 20 degrees above normal for a change for the
first half of next week.

Right now...the upper pattern looks like it did all of
February...with a ridge over the West Coast and a trough over eastern
noam...with an impressive winter storm still ongoing to the east of
the trough along the eastern Seaboard. Over the weekend...the western ridge
will remain...but the eastern trough will be lifting north...allowing
for a modification in the airmass. As we work through next
week...the ridge starts working east...which will allow for a
significant increase in heights...a more zonal flow...and
significantly warmer air to enter the region.

For the weekend...the two waves of interest are coming down Friday
night and Saturday night. In both cases...they will be fast moving
and limited on moisture. The first wave will have an attendant surface
low going across the international border and Lake Superior...so
expect any precipitation with this to remain primarily north of I-94...so
limited probability of precipitation Friday night into Saturday morning to areas mainly
along and north of I-94. We will have a brief cool down in the wake
of this system for Saturday...though highs will only be a few degrees
cooler than Friday and right near seasonal norms. The Saturday night
wave looks to be the stronger of the two...though we are seeing two
camps when in comes to precipitation potential across the mpx area. The
NCEP models /including the sref/ keep the mpx area mainly
dry...while the European model (ecmwf) and Canadian show a nice burst of snow to the
tune of 1-3 inches. The differences look to Stem from how far south
energy from a wave going across The Arrowhead will extend...with the
more bullish models brining the shortwave energy farther south. For
Sunday night...kept probability of precipitation at 30s or less in place...just oriented the
chance probability of precipitation area to be more in line with where the European model (ecmwf) shows the
snow falling.

For next week...as the western ridge begins to slide east...we will see
the upper jet and attendant storm track lifting north into
Canada...which looks to keep US dry most of the week. As the ridge
builds in we will see a significant increase in low level
temperatures...with the European model (ecmwf) showing 925 temperatures building to between 10c and
14c Tuesday and Wednesday. The question Monday through Wednesday is
how deep will we mix. The European model (ecmwf) continues to show that mixing
extending up to at least 925mb...with that resulting in highs in the
upper 50s to middle 60s. The GFS keeps mixing pretty shallow /like
around 950 mb/. This would mean much of this warming GOES into
building a strong inversion...with highs holding about 10 degrees
cooler than what the European model (ecmwf) has. With blended forecast used...the
European model (ecmwf) is out on its own...so current forecast is more in line with
the GFS. Beside those warm highs...SW winds through the overnight
hours will likely hold temperatures up near or above 30 Monday and Tuesday
nights...so we will be starting the melt next week.

&&

Aviation...(for the 00z tafs through 00z Friday evening)
issued at 607 PM CST Thursday Mar 5 2015

High confidence in VFR with no aviation weather concerns.

Kmsp...

High confidence in VFR with a light wind out of the south-
southwest.

/Outlook for kmsp/
Sat...VFR. Winds northwest 10 kts.
Sun...mainly VFR. MVFR ceilings possible with slight chance -rasn.
Winds west 10 kts.
Monday...VFR. Winds SW 10 kts.

&&

Mpx watches/warnings/advisories...
Minnesota...none.
WI...none.
&&

$$

Short term...jpc
long term...mpg
aviation...clf

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