Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Duluth Minnesota
300 am CDT sun Aug 30 2015

Short term...(today through monday)
issued at 257 am CDT sun Aug 30 2015

One the short term concerns will be the amount of smoke over the
region today and Monday and how that impacts temperatures. A weak
cold front will also move into western Minnesota Monday afternoon
bringing a threat for showers/storms to our western zones.

An upper ridge will move over the Northland today and pass to the
east tonight into Monday morning. Stratus and fog were expanding
this morning and the rap/hrrr both show this trend continuing
overnight...then thinning by 18z. A look at yesterdays visible
satellite showed plenty of smoke over the northern/Central Plains
into portions of Minnesota. We are concerned that we will see enough
smoke to limit sunshine today. We trimmed highs a bit today thinking
the smoke will be present and we also beefed up cloud cover since
smoke will give the appearance of high clouds. If the smoke is
thinner than expected...highs will have to be bumped back up. We
have highs today from the upper seventies to middle eighties.

We expect clouds to increase Monday ahead of the cold front...and
some smoke will once again be present. We have highs from 80 to 85
for most areas. There will also be a slight chance for some
afternoon showers/storms over western areas of the Northland.

Long term...(monday night through saturday)
issued at 257 am CDT sun Aug 30 2015

Warm and humid through the first week of September with chances for
an isolated storm most days. Little change to the previous forecast
with above normal confidence in the overall pattern. Storm chances
each day are fairly low...with the best chance for widespread
showers and storms late in the week into the weekend as a cold front
moves through from west to east.

On the synoptic scale a longwave trough will deepen in the west
while a weak ridge develops over the east...resulting in
southwesterly flow aloft for the upper Midwest. This will place the
region within the storm track for a few weak middle-level impulses
through the week. At the surface a warm front will lift north across
the region on Wednesday into Wednesday night...and following this
storm coverage will likely be limited Thursday/Friday afternoon until
Friday night and through the weekend as a cold front moves through
from west to east. Ahead of the front winds will be breezy out of
the south...with a very humid warm sector in place as dew points
rise to near 70. Storms this weekend could have the potential to be
strong to severe due to fairly steep middle-level lapse rates which
will aide in instability and stronger middle/upper level winds leading
to better deep layer shear. Not confident enough to mention this in
the severe weather potential statement just yet...but should the right factors align this is a

Highs through the week and into the weekend in the low to middle
80s...except for 70s by Lake Superior. Lows in the middle 50s to low
60s on nights when skies clear...otherwise in the middle to upper 60s
due to cloud cover. Winds predominately out of the south...becoming
gusty on Thursday Friday and even Saturday ahead of the cold


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1232 am CDT sun Aug 30 2015

Moisture will race north to northeast across the Northland a southerly low level jet develops across the central portion
of the country. The hrrr and rap continue to indicate that low
clouds and fog will hit the southeast half of the forecast area the
hardest...with IFR/LIFR conditions developing overnight. There is a
bit lower confidence for khib and kinl.


Preliminary point temps/pops...
dlh 81 64 84 64 / 0 10 10 30
inl 85 64 84 55 / 0 10 20 20
brd 83 65 85 60 / 0 10 10 20
hyr 80 62 83 65 / 0 0 0 20
asx 84 63 86 65 / 0 0 0 20


Dlh watches/warnings/advisories...


Short term...melde
long term...jjm

National Weather Service Glossary of Abbreviations