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Office: MPX

FXUS63 KMPX 211919
AFDMPX

Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
219 PM CDT Sun Oct 21 2018

.SHORT TERM...(This evening through Monday)
Issued at 230 PM CDT Sun Oct 21 2018

Little concern the near term.

Initial cold front/wind shift exiting to the east and weakening
during the evening. Will turn surface winds northwest across most
of central/southern MN into the evening before washing out. Weak
surface ridging moves in behind. With a clear sky and light winds,
the boundary layer should be able to radiate once again. It
should not be as cold as last night however, generally mid 20s to
lower 30s.

Models indicate a secondary cold front associated with a short
wave trough dropping across the western Great Lakes. It will
increase the pressure gradient and low level CAA pattern should
develop increasing the winds once again. Gusts to 25 kts possible
once again Monday afternoon. May see some low level clouds develop
and rotate over the northeast quadrant of the area as well. Highs
should range 50 to 55 across the northern CWA and 55 to 60 in the
south.


.LONG TERM...(Monday night through Sunday)
Issued at 230 PM CDT Sun Oct 21 2018

Forecast remains on track to be dry through Wednesday, but then it
appears that clouds and periods of light rain/drizzle will stick
move in Thursday and stick around through the weekend. Rainfall
amounts won't be very high, generally less than a half inch, but it
doesn't look like we'll have much if any sun.

A strong jet on the equatorward side of a powerful low pressure
system in the Gulf of Alaska will race eastward and cut through an
upper level ridge that is currently in place across the central
CONUS. This ridge is responsible for subsidence, high pressure, and
clear skies, but as it moves eastward we expect clouds to increase
late Wednesday and Thursday.

The increase in cloudiness is in response to a weak upper level
shortwave trough that will lift up from the Desert Southwest early
this week and move toward the Upper Midwest. Isentropic ascent ahead
of this shortwave will lead to gradual, widespread lift resulting in
clouds and light rain. Forecast sounding show clouds increasing from
west to east on Thursday, with a chance for light rain primarily
across southern Minnesota and southern Wisconsin.

Continued with a blended forecast for the end of the week as it
appears that the Upper Midwest will be stuck beneath an upper level
trough. This should allow the clouds and rain showers/drizzle to
persist through the weekend.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1145 AM CDT Sun Oct 21 2018

VFR SKC for this forecast period. Band of mid clouds exiting the
far east early. May see some stratocumulus develop Monday
afternoon. Gusty S-SW winds early afternoon becoming more W-NW
with passage of weak cold front. Then decreasing overnight and
mainly light west. NW winds will increase again Monday morning
and gusty again in the afternoon.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/
Mon night...VFR. Wind NW 5-10 kt.
Tue...VFR. Wind NW 5-10 kt.
Wed...VFR. Wind S at 5-10 kt.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
&&

$$

SHORT TERM...DWE
LONG TERM...DWE/JRB
AVIATION...DWE



Office: DLH FXUS63 KDLH 211958 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 258 PM CDT Sun Oct 21 2018 .SHORT TERM...(This evening through Monday) Issued at 258 PM CDT Sun Oct 21 2018 A weak cold front was moving through the forecast area at 19Z/2pm. The clouds that covered the eastern third of the area this morning, have moved out this afternoon. Drier air from high pressure was building across the region and will be overhead tonight. Light winds and clear skies expected. On Monday, the next cold front is progged to move through the region. Cold air advection will be strong in the afternoon. Some mixing is expected, before the clouds arrive, and will see some wind gusts to 25 mph. This will be a mainly rain free frontal passage with a lack of good moisture. However, models are pointing to an opportunity for some light rain showers over the Arrowhead in the afternoon. Will have a small chance pop to account for these indicators. Max temps will be below normal. .LONG TERM...(Monday night through Sunday) Issued at 258 PM CDT Sun Oct 21 2018 The upper air pattern will feature a big change later in the week, but before that occurs, the atmosphere will be dominated by a longwave trough over the eastern U. S. while a building ridge of high pressure will be to the west. That leaves the Northland a cool and dry northwest flow aloft and high pressure at the surface. This pattern will continue into midweek. In the meantime, a Gulf of Alaska upper closed low will eject a series of shortwaves that will affect the western Great Lakes Region from Wednesday night on through next weekend. As the first short wave moves across the region the surface low will develop in the central plains. Increasing southerly flow between the retreating surface high and western low will bring warmer and more moist air into the region and a chance of precipitation. The upper low will affect the region possibly through the weekend with rain or snow showers. All the extended models show the low closing off by Thursday evening...centered along the ND/Canadian border. && .AVIATION...(For the 18Z TAFS through 18Z Monday afternoon) Issued at 1233 PM CDT Sun Oct 21 2018 High pressure will keep conditions VFR for the forecast period. The exception is that there could be a lower ceiling late tomorrow morning in far northern MN with a forecast of ovc030. && .PRELIMINARY POINT TEMPS/POPS... DLH 30 48 30 40 / 0 0 0 0 INL 32 43 28 38 / 0 10 10 0 BRD 30 49 29 42 / 0 0 0 0 HYR 26 52 31 42 / 0 0 0 0 ASX 28 51 33 41 / 0 0 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...None. && $$ SHORT TERM...GSF LONG TERM...CLC AVIATION...CLC