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fxus63 kdlh 211139 

Area forecast discussion
National Weather Service Duluth Minnesota
639 am CDT Wed Aug 21 2019

issued at 637 am CDT Wed Aug 21 2019

Updated for the 12z aviation discussion.


Short term...(today through thursday)
issued at 430 am CDT Wed Aug 21 2019

An upper low was centered just west of James Bay this morning with
a shortwave diving southeast toward the Northland. This shortwave
will move through the region later today into tonight and we
expect an increase in cloud cover over far northern Minnesota this
afternoon and but we expect dry conditions. Cooler temperatures
have moved into the region and highs today will range from 65 to
70 over far northern Minnesota, to 70 to 75 from the Brainerd
lakes into northwest Wisconsin.

The shortwave will continue through the Northland tonight and
again we kept the forecast dry. We expect lows in the forties for
most areas and would have gone colder over far northern Minnesota
including The Arrowhead and Iron Range but there will be at least
some clouds around due to the shortwave.

Surface high pressure will move east on Thursday causing surface
winds to become east to northeast. Speeds will be less than 10 mph
for most areas but be locally higher in the twin ports area. We
expect more clouds due to an increasing cumulus field with surface
heating. It will be another cool day with highs in the mid
sixties to around seventy.

Long term...(thursday night through tuesday)
issued at 257 am CDT Wed Aug 21 2019

Cool and dry start to the long term with high pressure over the
region. Low temperatures on Thursday night could lower into the
upper 30s to low 40s east of the Iron Range and Gogebic Range
due to clear skies and cool air advected in. As the high
moves eastward, temperatures begin to warm into this weekend as
developing southerly flow advects warm, moist air to the upper
Midwest. Model guidance has been trending a slower progression of
the next chance for rain for this weekend keeping an upper ridge and
drier air over the northern plains stalling the longwave trough
attempting to build in and its associated shortwaves. Best chance
for precipitation now looks like it will occur from Saturday
night into Monday. On Monday, guidance is in agreement of
developing a surface low over Manitoba but differ in location and
track. Due to the influx of warm, moist air, upper level pattern
and surface cold front, there could be a potential for strong to
severe storm development on Sunday/Monday. With showers and
thunderstorms lingering over the area from Sunday to potentially
into Tuesday and precipitable water values approaching 2 inches, may also have to
monitor heavy rain and flooding potential.


Aviation...(for the 12z tafs through 12z Thursday morning)
issued at 637 am CDT Wed Aug 21 2019

After the fog lifts in the next couple of hours, VFR conditions
prevail through the taf period as high pressure builds into the
region. Breezy winds develop this afternoon with gusts of 15-20kts
possible. A few cumulus clouds may develop in the afternoon.
Clouds increase across northern Minnesota ahead of an upper level
disturbance moving through southern Ontario tonight.


issued at 257 am CDT Wed Aug 21 2019

No hazardous marine conditions are expected for the next 48
hours. Westerly winds today shift to north-northeasterly on
Thursday as high pressure builds into the region. Winds will
generally be less than 12 knots through this period, with waves of 2
feet or less.


Preliminary point temps/pops...
dlh 72 47 68 47 / 0 0 0 0
inl 67 45 66 48 / 0 0 0 0
brd 72 47 70 49 / 0 0 0 0
hyr 73 48 69 47 / 0 0 0 0
asx 73 50 67 45 / 0 10 10 0


Dlh watches/warnings/advisories...


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