Area forecast discussion
National Weather Service Duluth Minnesota
1221 am CDT Wednesday Jun 19 2013
Aviation...06z taf issuance,.
VFR conditions are in store for the Northland for much of the
night and even into Wednesday and Wednesday night. The exceptions
will be some possible localized fog overnight...and in the
presence of some spotty showers on Wednesday afternoon and
evening. There may even be a few thunderstorms...but confidence in
the storms being at taf sites that far out is fairly small so will
hold with showers for now.
&&
Previous discussion... /issued 733 PM CDT Tuesday Jun 18 2013/
Aviation.../00z taf issuance/
VFR conditions will prevail throughout the taf period...although
there could be some localized fog overnight. This could result in
localized IFR/MVFR if it materializes. Some spotty showers will
move across mainly the north on Wednesday. In fact...there may
even be a few thunderstorms but confidence not high enough yet to
include in the taf for that far out.
Previous discussion... /issued 305 PM CDT Tuesday Jun 18 2013/
Short term.../now - Wednesday/
The main focus is on the threat of showers and storms for
Wednesday. Since the GFS/Gem/NAM/ECMWF/sref/WRF all continue to
indicate some showers and storms Wednesday...mainly across NE
Minnesota...I continued to provide low chances of precipitation across
much of the forecast area for tomorrow. If any storms do
develop in the low capped warm and moist southerly flow...I would
not be surprised if one or two are strong with small hail and
brief heavy rain.
At 300pm/2000z...high pressure was centered over the western Great
Lakes...which was providing sunny skies for most of the Northland.
Temperatures across NE Minnesota and northwest Wisconsin ranged from the
middle 60s to lower 70s with the coolest temperatures near Lake
Superior. The winds were light from the south and east.
Through tonight...the high pressure should continue to provide
clear to mostly clear skies. Overnight lows should range from the
lower 40s to lower 50s...but there could be isolated areas that
dip into the 30s because of the relatively low dew points that
developed this afternoon.
Wednesday...low pressure will begin to strengthen in the High
Plains...and this will result in increasing southerly winds across
the Northland. The warm and moist flow will give a low threat of
showers and storms for most of the Northland...primarily NE
Minnesota...late in the morning and through at least the
afternoon. If any storms develop...they are expected to be less
than severe. However...there could be an isolated strong storm or
two that could have small hail and brief heavy rain. The
nam12/GFS/sref are indicating a good potential of at least 500 to
1500 j/kg of cape for the western and northern forecast area. Deep
layer shear (0-6 km) will be about 25 to 35 knots. If there was a
frontal boundary or other significant mechanism to initiate
storms...I would be more concerned about a little severe weather.
I raised the high temperature forecast a bit based on a blend of
the latest model guidance. High temperatures will likely range
from the middle 60s to upper 70s with the coldest temperatures along
the immediate shoreline of Lake Superior.
Long term.../Wednesday night - Monday/
North active patter
continues through the end of the week. The next shortwave will
affect the forecast area will move through southern Minnesota as
warm moist area continues to flow into the region. Dewpoints
will reach the lower 60s across most of the area. Thunderstorms
will develop late Thursday afternoon and spread east Thursday
evening the area west of a dlh-inl line is under a slight risk
from Storm Prediction Center. The rest of the area is under a 5% probability for sunrise weather
for Thursday. MUCAPES are forecast to be in the 1500-2500 j/kg
range with lifted indice's in the -2 to -4 range. The thunderstorms will end
west to east after midnight Thursday night giving the area a break
until late Friday afternoon.
On Friday...an area of low pressure will move through northern
Nebraska to southern Minnesota by Saturday morning. The warm and moist
flow will continue across the forecast area with dewpoints
remaining in the lower to middle 60s. Thunderstorms will develop
late Friday afternoon and affect the region into Saturday. Showers
and thunderstorms will be most likely across the Brainerd lakes
area 00z-12z Sat...the Iron Range and twin ports 03z-15z...and northwest
WI 05z-17z Sat. Some of the storms could be strong with MUCAPES
1500-2500 and lifted indice's -2 to -5. The precipitation will taper off
toward late afternoon of Saturday. Another shortwave will move
through on Sunday giving the area another chance for
thunderstorms.
&&
Point temps/pops...
dlh 73 56 75 55 / 20 30 50 60
inl 76 55 79 58 / 40 30 50 70
brd 78 60 80 63 / 30 30 60 70
hyr 74 57 79 60 / 10 30 50 70
asx 74 56 75 55 / 10 30 50 70
&&
Dlh watches/warnings/advisories...
Minnesota...none.
WI...none.
Ls...none.
&&
$$
Aviation...dap
