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Area forecast discussion 
National Weather Service Duluth Minnesota
1232 am CDT Thursday Jul 30 2015

issued at 1232 am CDT Thursday Jul 30 2015

Updated for the 06z aviation discussion below.

Update issued at 947 PM CDT Wednesday Jul 29 2015

Clouds and showers continue to decrease as of middle evening. The
most cloud cover at this time was across the far north. Zones and
grids appear to be in good shape...and only minor changes have
been made for the evening update.


Short term...(this evening through thursday)
issued at 308 PM CDT Wednesday Jul 29 2015

An unusually deep area of low pressure over far northwest Ontario will
continue to cause gusty westerly winds across the Northland
through early this evening. Expect widespread wind gusts of 25 to
40 miles per hour. There could be stray gusts to 45 miles per hour in NE Minnesota late
this afternoon.

Much of the forecast area had broken/overcast cloud cover due to the
instability caused by the cool and relatively humid westerly
flow. This cloud cover should gradually diminish this evening and
overnight as heights increase as the low lifts into Hudson Bay.
Several models are indicating low potential for precipitation across the
northern forecast area through tonight...including the
nam12/gemreg/sref/WRF. Light rain is possible across the
Borderland and arrowhead through tonight...with chances gradually
diminishing overnight. Despite the overnight clearing...leaned on
the slightly warmer guidance since the overnight winds should help
bolster the temperatures.

The Northland will remain in northwest flow aloft on Thursday. The day
should be warmer and sunnier. The nam12/GFS soundings indicate
the likelihood of widespread 20 to 25 miles per hour wind gusts during the
afternoon and early evening based on the winds in the mixing
layers in the soundings. The nam12/GFS soundings also suggest the
convective temperatures should be low enough to pop scattered
cumulus by the afternoon. Several models are indicating the
potential for afternoon showers and weak storms...including the
nam12/gemreg/GFS/WRF/sref models. This is mostly for the far
northern forecast area...and near and east of Highway 13 in northwest
Wisconsin. The nam12/sref are indicating the potential for up to
several hundred j/kg of mixed layer there could be a
stray stronger cell. The more prominent showers and storms could
end up producing gusty winds...potentially up to 40 miles per hour. Highs
should be in the upper 70s to low 80s.

Long term...(thursday night through wednesday)
issued at 308 PM CDT Wednesday Jul 29 2015

A fast northwest flow aloft will affect the forecast area Thursday night
through Tuesday. In this flow...pieces of short wave energy will
rotate through the area Friday and Saturday night through Tuesday.
With these pieces of energy...a few showers and isolated
thunderstorms will occur over parts of the region and have probability of precipitation
aligned to account for these impulses. Between these short
waves...periods of dry weather will be found. Temperatures during
this period will be near normal.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1232 am CDT Thursday Jul 30 2015

VFR conditions expected at all terminals through the forecast
period. Gusty winds will develop at all terminals between 14z and
15z. Latest guidance brings a shortwave into northern Minnesota
during the 18z to 06z time frame from central Saskatchewan. The
shortwave combined with day time heating will bring a threat of
scattered showers and thunderstorms to inl...hib and hyr between
19z and 02z. Due to the scattered nature...kept as vcsh. Once the
night time inversion sets up winds will decrease between 00z and


Preliminary point temps/pops...
dlh 60 78 58 79 / 10 0 0 10
inl 53 76 50 78 / 10 20 10 10
brd 59 80 54 82 / 10 0 0 10
hyr 56 77 53 79 / 10 0 0 10
asx 59 78 56 77 / 10 0 0 10


Dlh watches/warnings/advisories...
Ls...Small Craft Advisory until 10 PM CDT this evening for lsz121-



short term...grochocinski
long term...gsf

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