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fxus63 kdlh 290536 
afddlh

Area forecast discussion
National Weather Service Duluth Minnesota
1236 am CDT Thu Jun 29 2017

Update...
issued at 1227 am CDT Thu Jun 29 2017

Updated aviation section below for the 06z taf issuance.

&&

Short term...(this evening through thursday)
issued at 420 PM CDT Wed Jun 28 2017

Main concerns for the short term are the small risk of severe
thunderstorms this evening and heavy rainfall potential.

Surface low pressure was centered near Park Rapids this afternoon
with a warm front extending southeastward through the Twin Cities
and a cool front stretched south over western Minnesota. Several
lobes of vorticity were evident in water vapor imagery and
regional radar. Thunderstorms have begun to redevelop along the
warm front near the Twin Cities within the last hour. Storms
should become more numerous and advance east-northeastward toward
our southernmost Wisconsin zones. Strong to severe storms are
possible, especially south of a line from Pine City to Hayward to
Park Falls. The high-resolution hourly models suggest the 850 mb
Theta-East Ridge will pivot along our southern border with robust
moisture advection into that area. Heavy rainfall is still a
threat the storms tonight, along with a small risk of flash
flooding. Heavy rainfall is also expected in north-central and
northeast Minnesota as the upper low over northwest Minnesota
wobbles eastward during the next several hours. While rainfall
amounts of 1 to 2 inches are likely, the shallower terrain should
lead to a slower response and lower flash flood risk. Localized
minor flooding and ponding of water will be a concern tonight as
the upper low slides eastward tonight.

The low pressure will move out of the Northland tonight with
showers lingering in northeast Minnesota for much of the day
Thursday. Another area of low pressure aloft will begin to push
into our western zones during the afternoon hours with scattered
showers and isolated storms possible.

Long term...(thursday night through wednesday)
issued at 420 PM CDT Wed Jun 28 2017

With a semi-permanent upper trough over the western Canadian
provinces, the northwest flow will continue, which will give the
Northland cool temperatures and rounds of showers and
thundershowers.

In the shorter term, by Thursday evening the surface low that is
bringing all the rain today will be over southern Ontario, but the
upper low will still be over Lake Superior, which will be keeping
the Northland in cyclonic flow. The showers that pop up in the
afternoon will likely linger though the night. These will be
reinforced by another upper low that will give another round of
rain Friday and Saturday and into Sunday. It looks like we can say
confidently that our next dry day won't be until next Monday and
Tuesday when the Northland will be between low pressure systems:
one pulling off to the east and another forming in the Lee of The
Rockies in response to yet another upper level low pressure
trough.

&&

Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1227 am CDT Thu Jun 29 2017

Low pressure system over the Northland this evening has brought
an area of widespread rain showers affecting most of the
terminals, along with a mixture of LIFR to MVFR conditions for
most locations. This pattern to continue through much of the next
6-12 hours, with gradual improvement to at least MVFR/VFR by 18z.
All sites should be VFR by 00z.

&&

Preliminary point temps/pops...
dlh 54 71 54 66 / 80 10 30 50
inl 55 72 55 69 / 80 10 40 60
brd 58 77 58 71 / 20 20 50 60
hyr 58 72 54 70 / 70 10 30 50
asx 54 70 53 68 / 70 20 20 40

&&

Dlh watches/warnings/advisories...
WI...none.
Minnesota...none.
Ls...Small Craft Advisory until 4 am CDT early this morning for
lsz140>145.

&&

$$

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