Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Duluth Minnesota
405 am CDT Monday may 25 2015

Short term...(today through Tuesday afternoon)
issued at 403 am CDT Monday may 25 2015

Widespread light rain showers continue across the Northland this
morning and will be the main focus of attention in the short term
today and tonight. Another round of showers...and isolated
thunderstorms will be possible Tuesday afternoon especially over
northwest Wisconsin.

Upper low continues to rotate eastward from the central rockies into
the plains and upper Midwest this morning with a preceding surface
low lifting to the NE into southern Minnesota. Broad large scale lift from an
embedded short wave combined with a band of middle-level f-general have been the
primary forcing mechanisms producing the widespread rain showers
across the region last night and early this morning. The surface low
will continue to move to the NE today and as the upper low catches
up from the enhanced area of precipitation will develop across
the deformation zone over northern/northestern Minnesota and allow for an additional
inch of rainfall to occur over the region. Have seen reports of a
third to three quarters of an inch so far this morning. Mainly
south of U.S. Highway 2.

Conditions should remain fairly stable and keep the precipitation in the
form of stratiform rain today and into tonight. The low will move
out of the area later today...but also keep a trailing trough/cold
front behind across Western Lake Superior tonight and keep the rain
showers going into this evening. Weak high pressure will build in
from the west tonight on the northern edge of approaching inverted
trough. This incoming trough will move eastward into the Great Lakes
and brush portions of the Northland with additional rain showers
and even a few scattered thunderstorms. The greatest threat will be
over northwest WI Tuesday afternoon.

Temperatures will remain on the cool side today with highs in the
50s and 60s. The coolest air will be found around Lake Superior
where a NE wind off Lake Superior will keep conditions in the low
to middle 50s. Warmer air will be found away from the lake...with
mainly middle to upper 60s. Lows tonight will drop into the 40s and
50s. Highs on Tuesday will warm into the 60s and 70s...with the
cooler temperatures to the east under the cloud cover...and slightly
warmer to the west where clouds are expected to scatter out in the

Long term...(tuesday night through sunday)
issued at 403 am CDT Monday may 25 2015

The extended time period will start out a bit unsettled...but will
transition toward a mainly dry period for the weekend. Low pressure
will exit the Northland on Tuesday night...with lingering showers in
northwestern Wisconsin. Will continue to mention a chance of showers
and thunderstorms on Wednesday...mainly in the there
will be some instability across the area. The best chance of seeing
the precipitation should be in northern portions of the region.
Wednesday night will be a mainly dry period...although some spotty
showers could linger into the evening across The Arrowhead. The next
low pressure system will already be advancing into the northern
plains later Wednesday night. A few showers and thunderstorms are
expected to move into our extreme west late in the night as showers
and thunderstorms develop in the Red River valley. This chance of
showers and thunderstorms will move into the County Warning Area on Thursday...but
the most organized and widespread precipitation is expected Thursday
night and Friday. With Canadian high pressure building into the
region on is looking like the weekend should be on the
dry side. The GFS does bring fairly widespread precipitation into
the southeast half of the County Warning Area on Sunday...but the European model (ecmwf) is dry. Tendency at
this point is to side with the European model (ecmwf) due to the strength of the high
over the Great Lakes. Wednesday is looking to be the warmest day of
the week...with high temperatures reaching right around 80. For the
rest of the week...high temperatures should settle back into the 60s
to lower 70s.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1228 am CDT Monday may 25 2015

Conditions for kdlh...kbrd...and khyr continue to deteriorate to
IFR ceilings and MVFR visibilities as an area of rain continues to
spread up into the area from the south. Khib to be on the edges of
the lower ceilings...and should mainly remain MVFR. Widespread IFR
ceilings...once they develop...should continue through much of the
remainder of the taf period...with only slow improvement after 21z
to MVFR for kbrd.


Preliminary point temps/pops...
dlh 56 49 68 48 / 90 50 20 20
inl 72 49 79 49 / 30 30 20 20
brd 61 50 72 52 / 90 50 10 10
hyr 64 51 69 49 / 90 40 40 40
asx 55 47 65 45 / 90 40 40 30


Dlh watches/warnings/advisories...
Ls...Small Craft Advisory from 10 am this morning to 4 PM CDT this
afternoon for lsz142>147.



Short term...bjt
long term...dap

National Weather Service Glossary of Abbreviations