Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Duluth Minnesota
1243 am CDT Monday Mar 30 2015
Short term...(this evening through Monday night)
issued at 313 PM CDT sun Mar 29 2015
At 310 PM...the Northland had gusty northwest winds due to the earlier
passage of a strong cold front. The winds were gusting to 25 to 35
miles per hour over most of the region...and in some areas nearly 40 miles per hour. The
eastern forecast area had cloudy skies...but there was clearing
over the western areas. Temperatures ranged from the lower 30s
over the far east to the middle to upper 40s over the west.
The gusty winds and clearing trend will continue through this
evening. High pressure will begin to move into the region from
the west tonight...leading to mostly clear skies and light winds
overnight. Overnight lows should be in the upper 20s to low 30s.
A low pressure trough will move into the northern plains and
Minnesota/Wisconsin region Monday. While the morning will likely
begin rather sunny...there will be increasing cloud cover and
chances of light rain during the late morning and afternoon. The
models suggest this band could be focused along a low/middle level
frontogenetical band that will move across the Northland with the
trough boundary. High temperatures will be cooler in the upper
30s and lower 40s over the NE forecast area due to the cloud
cover and rain...but could reach the upper 50s in the SW where
there will be more sun.
Long term...(tuesday through sunday)
issued at 313 PM CDT sun Mar 29 2015
An elongated area of vorticity will move over the region Monday
night. This will bring an opportunity for some mixed
precipitation. Snow is forecast for The Arrowhead where up to one
inch is possible. One more piece of vorticity clips The Arrowhead
Tuesday morning...but a warming low level will lead to a
rain/snow mix. By Tuesday afternoon...the vorticity maximum moves off and
high pressure builds over the area and lingers through Tuesday
night. On Wednesday...warm air advection is underway ahead of a surface low moving
through south central Canada. Timing differences emerge amongst
the models as well as quantitative precipitation forecast coverage. Instability increases through
the day ahead of a cold front near the Minnesota/Dakotas border by late
morning. Some showers may break out along the international
border and on the tip of low level jet moving through southern Minnesota. Models
have been consistent with the development of thunderstorms in the
afternoon as the cold front moves into the area. Have added an
isolated mention of thunder ahead of the front where ingredients for
storms are organizing. The front moves into northwest WI Wednesday
evening and have added isolated thunder to northwest WI. The instability
moves east of the area late Wednesday night and have no mention of
thunder after 06z...but still expect some showers. On
Thursday...the surface low moves into northwest Ontario with a surge of cold
air behind it. Lowest levels should remain warm enough for rain.
Thursday night any lingering precipitation will be snow as deeper cold air
arrives with 850 mb temperatures dropping to -11c over much of the area.
Model differences become pronounced as a an anticipated series of
upper level short waves are prognosticated to affect the area. Air will
be cold enough for any precipitation to be all snow.
Aviation...(for the 06z tafs through 06z Monday night)
issued at 1242 am CDT Monday Mar 30 2015
VFR conditions throughout all taf sites this evening. VFR ceilings
will continue at all sites overnight...however there still will be
periods of scattered skies from time to time. Winds have subsided as
pressure gradient has relaxed. Added some light fog for khib and
kinl terminals overnight due to light winds and recent precipitation.
Another low will move into the region from the northwest on Monday.
Model soundings support rain as the precipitation type throughout this
period...with the exception being over The Arrowhead which may be
cold enough for snow late in the period.
Last several hrrr runs keep precipitation to the north of kbrd. Felt
confident enough to keep -ra out. All other taf sites should see -ra
prevail late in the period as h850 fgen moves in from SW to NE as
the low strengthens. MVFR ceilings are possible at all terminals
except for kbrd during this time frame.
Preliminary point temps/pops...
dlh 32 51 36 61 / 50 10 0 30
inl 28 49 33 63 / 50 10 10 20
brd 35 58 42 68 / 10 0 0 10
hyr 29 54 33 65 / 30 0 0 40
asx 28 47 33 61 / 40 10 0 30