Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1049 PM CDT Thursday Oct 8 2015
Short term...(this evening through friday)
issued at 250 PM CDT Thursday Oct 8 2015
Early this morning a 50/100 Mile band of rain showers and embedded thunderstorms and rain
extended from krwf...NE to St. Cloud and northern WI. This was
associated with strong moisture advection along the leading edge of
a shortwave across northwest Minnesota. Surface winds had begun to gust along the
Buffalo Ridge in wc Minnesota where temperatures rose into the middle/upper 60s where
a warm front was located. The main cold front was in eastern ND
which will rapidly move southeast across Minnesota during the morning.
Current weather/pop grids seem reasonable based on the latest rap/hrrr
that has a narrow band of rain showers/thunderstorms and rain moving across most of Minnesota by 12-
14z. Only wc WI...southeast of Hudson to Ladysmith will have any
substantial morning rainfall after sunrise. There remains the
possibility of sprinkles/-shra moving southward across central Minnesota
during the late morning as instability rain showers develop as the main
shortwave moves overhead. Although the moisture depth associated
with the shortwave is shallow...later shifts will need to monitor if
scattered rain showers are need to be included later this morning/afternoon for
portions of central/ec Minnesota and wc WI. Temperatures may actually begin to
fall during the day as cloud cover increases from the north/northwest and cold air advection
becomes strong behind this shortwave.
Long term...(friday night through thursday)
issued at 250 PM CDT Thursday Oct 8 2015
Record warmth remains possible Sunday as very seasonably warm
airmass moves across there region...with southwest winds setting
up a favorable profile for temperatures exceeding guidance. The
dry trend also will continue through next week as the main storm
track sets up across the north.
Not much change from the previous forecast. Forecast guidance
continues to show warm temperatures...and mixing down from around
900mb shows record highs possible on Sunday. The NAM guidance has
a few 90s across the upper Minnesota River Valley. Fairly high
confidence that skies will be clear Sunday...but forecast
soundings show a lull in the winds...which would limit the mixing
and temperature potential somewhat. For now have 84 at msp...which
would tie the record...and less than record values at stc and eau.
Looking ahead..forecast soundings show very windy conditions on
Monday...and the winds in the grids will need to be adjusted up
if this trend continues. Would not be surprised to see gusts in
excess of 40 miles per hour. The cool temperatures aloft could result in a
stray shower Monday afternoon...so have 15 to 20 percent chance.
Once this exits the region warm weather will continue with highs
in the middle 60s.
Aviation...(for the 06z tafs through 06z Friday night)
issued at 1049 PM CDT Thursday Oct 8 2015
Drier low level air flowing in from the north has helped raise
ceilings to around 030-035 late this evening. Little in the way of
clearing is evident in satellite. With the incoming ridge from the
Dakotas overnight...it/S likely that the cloudiness will linger
through the night...especially across western Minnesota. An exception is
across eastern Minnesota and western WI where some clearing may work in
late tonight from kdlh. Tough call on Friday with a negative cumulus
rule forecast by the NAM and rap. Therefore kept broken VFR ceilings
through much of the morning before going scattered in the
afternoon. North to northwest winds 8-12 knots overnight becoming
northwest 5-8 knots Friday morning and then backing to the south-southwest by
Kmsp...ceiling should become ovc035 by 08z if not sooner. Bkn035-040
expected in the morning with sct040 in the afternoon. Winds
similar to those described above.
/Outlook for kmsp/
Sat...VFR. Winds south-southwest 15-20g25 kts.
Sun...VFR. Winds south-southwest 10-15 kts.
Monday...VFR. Winds northwest 20-25g30 kts.