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Area forecast discussion 
National Weather Service Duluth Minnesota
657 PM CDT Sat Apr 18 2015

Update...
issued at 651 PM CDT Sat Apr 18 2015

Updated aviation section below.

&&

Short term...(this evening through Sunday night)
issued at 320 PM CDT Sat Apr 18 2015

A warm and dry week comes to an end with rain and cooler
temperatures late Saturday night into Sunday.

On the synoptic scale an area of high pressure over the upper Great
Lakes/southern Ontario is leading to easterly flow across Lake
Superior...and thus cooler temperatures near the Lake. Two areas of low
pressure to the west...one over southern Saskatchewan and the other
in northeast Colorado...will move east towards the Midwest tonight.
Ahead of this southern system moisture will increase throughout the
column...with precipitable water values approaching an inch. Strong fgen across
northern Minnesota will lead to widespread rainfall late tonight and
continuing through Sunday morning. On Sunday dry slot may build in
to central and northern Minnesota with the best chance of precipitation
existing across northwest Wisconsin.

Rest of today...sunny...dry...and mild. Winds inland have been a bit
stronger than originally forecast due to deeper than expected mixing
occurring...but otherwise previous forecast was well on track. Temperatures
by Lake Superior have been much cooler as expected...in the low to
middle 40s along the coast...and warmer in the upper 50s to middle 60s
inland. Dry out there...relative humidity values falling to 15 to 25
percent across northern Minnesota and portions of inland northwest
Wisconsin.

Tonight...increasing clouds early...rain after midnight. Rain may be
heavy at times. As lows dip to the middle 30s to low 40s could see some
snow mixing in at times...mainly across the higher terrain of the
Minnesota arrowhead region. Rain will be most intense towards early
Sunday.

Sunday...cloudy...off and on rain...and generally cooler. As cold
front moves through from west to east will see off and on rain
showers...but generally a downward trend in coverage and intensity of
precipitation. Temperatures feeling much cooler but really about average for this
time of year in the middle 40s to middle 50s.

Long term...(monday through saturday)
issued at 320 PM CDT Sat Apr 18 2015

The extended period will be dominated by an upper level low over and
near the Northland through middle to late week.

An elongated area of low pressure...frontal boundary and an upper
trough will all cause rain to continue Sunday evening over far
eastern areas. Most of the models are now in agreement with a dry
slot bringing an end or minimum to the precipitation over central/western
areas through much of the night. Colder air will move in Sunday
night behind the cold front/surface low and some snow will be
possible over northern areas late. Little accumulation is expected
overnight.

We ramped up probability of precipitation Monday and kept them likely over much of the
Northland into Monday night with the upper low over the Northland. A
mix of rain and snow will be possible with mainly snow over northern
areas at least through the morning. Some light snow accumulation is
expected Monday/Monday night...possibly 1 to 3 inches over far
northern Minnesota.

The chance for rain/snow will continue Tuesday then diminish from
west to east Wednesday into Thursday.

Outside of some lake effect precipitation Thursday and Friday...dry weather
is expected after Wednesday.

Temperatures will be around 10 degrees below normal Monday through
Thursday then warm to near normal by Saturday.

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 651 PM CDT Sat Apr 18 2015

An area of low pressure will cause clouds to thicken this evening
and lower overnight into Sunday morning to IFR for most
areas. An area of rain will move up from the south tonight and
continue into Sunday morning...bringing MVFR visibilities. Gusty
east/southeast winds this afternoon will diminish this
evening...except for kdlh. As area of rain moves back out of the
area after 18z ceilings will remain low for a few more hours even
as visibilities begin to improve and winds switch from southeast
to west.

&&

Preliminary point temps/pops...
dlh 39 49 36 42 / 90 90 40 60
inl 38 49 32 40 / 100 100 50 70
brd 44 55 36 42 / 100 90 20 60
hyr 45 56 37 44 / 50 90 60 50
asx 41 56 38 45 / 60 80 60 50

&&

Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...Small Craft Advisory until 10 am CDT Sunday for lsz142>147.

Small Craft Advisory until 10 PM CDT this evening for lsz121-148.

&&

$$

Update...le
short term...jjm
long term...melde
aviation...le

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