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Area forecast discussion 
National Weather Service Twin Cities/Chanhassen Minnesota
728 PM CDT Wednesday Aug 31 2016

Update...
issued at 630 PM CDT Wed Aug 31 2016

Updated to include 00z aviation discussion below.

&&

Short term...(this evening through thursday)
issued at 315 PM CDT Wed Aug 31 2016

Quiet short term period ahead with mostly sunny skies and
seasonable temperatures across southern/central Minnesota and west
central WI. Elongated high pressure stretching north to south from
the Hudson Bay region through the upper Midwest this afternoon
will slowly move southeastward with time and stay in control of
our local weather through the short term forecast period.

Did use some bias corrected guidance to try and nail down the
overnight lows tonight under clear skies and light winds. Could
see some patchy fog develop again similar to last night, but
likely not widespread at this time. Overnight lows should fall
into the low to mid 50s, with a few low lying areas from Mille
Lacs Lake toward Rice Lake and Ladysmith, WI sneaking into the
upper 40s a possibility.

For tomorrow, winds turn southeast and we could see some scattered
cumulus clouds form. Still, another pleasant day ahead with
temperatures in the upper 70s west and lower 70s east.

Long term...(thursday night through wednesday)
issued at 315 PM CDT Wed Aug 31 2016

The influence of how Tropical Storm Hermine interacts with the
overall upper air pattern across the East Coast will play some
part in our extended forecast, especially late in the weekend.

First, models have forecast Hermine to move up to eastern Seaboard
through early next week. This may lead to a disruption of the
upper ridge building eastward across the upper Midwest. If this
occurs, this will lead to slowing of precipitation expected for
the first part of the weekend. Secondary, a long wave trough
across the west part of North America will continue to dig south
and east across the Pacific northwest, and northern rockies by
early next week. Between these two systems, our weather will be
predominately dry until a frontal boundary nears the area late
Sunday, and into early next week. This boundary will likely stall
or move very slowly eastward, which will lead to a continued
chance of precipitation for the upper Midwest from Monday through
Wednesday. Not until the long wave trough moves eastward over the
upper Midwest late next week, will the weather pattern become
cooler and more stable.

To sum things up, a quiet and breezy period from Friday through
Sunday will become more unsettled and wet for the first part of
next week.

Due to a prolonged period of wet weather early next week, the
potential of flooding increases, especially considering the amount
of rainfall our region has received the Summer. The cips extended
analog threat guidance suggests a high probability of 2-3 inches
of rainfall in the 6-8 day outlook period. Even the guidance
suggests the continuation of high rainfall amounts for days 9-11.
This will need to be address in future forecast for the possibility
of flash flooding, and river flooding. Another note on these cips
extended analogs is that a much cooler period is likely beyond day
10.

&&

Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 630 PM CDT Wed Aug 31 2016

VFR conditions to prevail under high pressure. Some patchy and
possibly IFR fog possible at both WI taf sites overnight into
early Thursday morning. Otherwise, after skies clear out tonight,
few-scattered high clouds will stream over the area tomorrow.

Kmsp...no significant weather concerns expected.

/Outlook for kmsp/
Friday...VFR. Wind south-southeast 5-10 kts.
Sat...VFR. Winds 10-15g20 late afternoon.
Sun...mainly VFR. MVFR/thunderstorms and rain possible. Wind S 10-15g20 kts.

&&

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

$$

Update...jpc
short term...speed
long term...jlt
aviation...jpc

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