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Area forecast discussion 
National Weather Service Duluth Minnesota
633 PM CDT Tuesday Mar 31 2015

issued at 632 PM CDT Tuesday Mar 31 2015

Updated aviation section below. Have also made some quick updates
to temperatures and winds for this evening.


Short term...(this evening through Wednesday night)
issued at 333 PM CDT Tuesday Mar 31 2015

At 330 PM...a weak area of low pressure was located over the Upper
Peninsula of Michigan. An area of high pressure was centered over
far northern Ontario. A weak ridge of high pressure was centered
from western Iowa to northern Minnesota. The Northland had 5 to 15
miles per hour northwest winds. Skies were primarily mostly sunny. Temperatures were
in the 50s...except the 40s in the northern arrowhead where there
was lingering broken/overcast cloud cover.

The winds will diminish this evening as the weak ridge of high
pressure shifts into the Northland from the west. Easterly and
then southeast winds will develop and increase later tonight as the
ridge of high pressure moves through the region and in response
to a strong low pressure system in the northern High Plains
moving into central North Dakota. Low temperatures will likely
range from the upper 20s in the eastern forecast area...but the
low and middle 30s over the west where the winds will bolster the

There could be fog and mix of snow and rain along the far North
Shore late tonight and Wednesday morning due to the humid winds
off of Lake Superior.

The low pressure system in the northern plains...which will be in
central North Dakota by sunrise Wednesday...will begin to lift to
the NE and merge with another low pressure system crossing east
across Saskatchewan and Manitoba Wednesday. The warm front
associated with this overall system will lift into the upper
Midwest. Strong...warm southerly flow will develop over most of
the Northland by late Wednesday morning. Winds will likely be 15
to 25 miles per hour with higher gusts. Easterly to NE flow over Lake
Superior will keep the North Shore and Duluth area close to Lake
Superior much cooler than more inland areas. Inland areas will
likely climb well into the 60s. There will be increasing chances
of showers Wednesday afternoon. There could also be some
thunderstorms. The best chance for storms appears to be near the
Interstate 35 corridor in NE Minnesota and east into northwest
Wisconsin. The instability looks limited due to the warm cap think the chances for any strong storms is very low
based on the latest information. The strong cold front will begin
racing into the western forecast area during the late afternoon.

Long term...(thursday through tuesday)
issued at 333 PM CDT Tuesday Mar 31 2015

Primary concern for the long term is approaching critical fire
weather conditions for Thursday and possibly Friday following a
cold front. Showers/isolated T-storms taper off quickly on
Wednesday night as surface low moves across northern Minnesota.
Thursday will be dry and breezy with another cold front moving
across. This next cold front looks to have a lot more middle/upper
level moisture associated with it...along with steep low/middle
level lapse rates and low but notable values of cape. These
factors combined with the good large-scale forcing have lead to
increased probability of precipitation for Thursday due to the possibility of showers and
possibly a thunderstorm or two. Following this system the weekend
looks generally dry though the northwesterly flow pattern aloft
could bring a weak upper disturbance our way. Next weather system
arrives early next week on Monday afternoon into Tuesday as a
Colorado low deepens and moves northeast across the Central
Plains into the Midwest.

Temperatures through the long term will be mild late in the week
to near to below normal over the weekend into early next week.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 632 PM CDT Tuesday Mar 31 2015

VFR conditions expected through at least 18z with east to southeast
winds at less than 10kts increasing to 10 to 15 kts with gusts to
20 kts after 12z. Kdlh may be affected by a more northeast flow
and some MVFR stratus flowing off Lake Superior. After 18z showers
are expected in vicinity of kdlh and khyr. Thunder is also
possible...but quite unlikely and have left out of terminal
forecast for now. For now am expecting MVFR ceilings and
visibilities with these showers.


Preliminary point temps/pops...
dlh 32 57 42 55 / 0 20 20 10
inl 31 63 39 47 / 0 0 20 30
brd 38 69 41 53 / 0 10 10 0
hyr 32 64 43 58 / 0 50 60 0
asx 29 62 42 58 / 0 30 40 0


Dlh watches/warnings/advisories...


short term...grochocinski
long term...jjm

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