Area Forecast Discussion
Issued by NWS Duluth, MN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS63 KDLH 190920

Area Forecast Discussion
National Weather Service Duluth MN
420 AM CDT Thu Oct 19 2017

.SHORT TERM...(Today through Friday)
Issued at 415 AM CDT Thu Oct 19 2017

The main concerns during the short-term involve heightened
wildfire risk over much of the Northland due to continued dry

A very dry airmass remains over the area early this morning.
Humidity values at 3 AM were anomalously low with readings in the
upper 20 percent range in the Arrowhead and along the Gogebic
Range in north-central Wisconsin and the low 60 percent range in
southern Cass and Pine Counties. Boundary layer moistening will
continue early this morning, but the day is expected to start off
drier than yesterday. Look for humidity values to fall rapidly
again today with dewpoints in the 20s and temperatures rising into
the low 60s northeast to low 70s in the St. Croix Valley. South
winds are forecast today but wind speeds will be lower, from 5 to
15 mph. A warm front is forecast to lift into the Northland this
afternoon which may buoy dewpoints in central Minnesota.

The boundary layer should remain mixed into this evening before
decoupling late overnight. Have kept temperatures a little warmer
tonight as a result. Plenty of support for keeping min temps
elevated based on the past two morning`s observations. Lowered
dewpoints and humidity values again for Friday as efficient mixing
and abundant dry air will remain in place. Anticipate mixing to
at least 900 mb for Friday, which would result in temperatures in
the middle to upper 70s across the forecast area. Moderated those
temps with a blend of bias corrected versions of the Hi-resolution
ARW and SREF guidance. The end result still yields upper 70s over
much of northwest Wisconsin into the St. Croix Valley in east-
central Minnesota. Lower to middle 70s are forecast across the
remainder of our Minnesota zones.

.LONG TERM...(Friday night through Wednesday)
Issued at 415 AM CDT Thu Oct 19 2017

Dry weather continues under a strong ridge through Saturday
morning. A strong push of high PW air arrives early Saturday
priming the atmosphere for thunderstorms Saturday afternoon. A
strong LLJ, and upper level vort max approaching, and weak
instability should be enough to kick off storms. For the showers
and storms that do develop, rainfall rates should be rather high
with PWs in the 1.5 inch range, which would be record values for
this time of year according to the SPC PW climatology. Even bulk
shear is supportive of stronger cells, so will have to keep an eye
on this day overall. One saving grace may be that dynamics are
even better to our south which could lead to storms developing
there and "stealing" the energy potential for our area.

By Sunday, the cold front that develops from the developing Saturday
system will be off to our east. A backside clipper will slide down
by Monday bringing a threat for mixed precip. A closed surface low
lingers just to our east through mid week.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1211 AM CDT Thu Oct 19 2017

VFR through the forecast. LLWS is expected to affect the
terminals at the start of the forecast with another LLJ nearby.
LLWS is possible again toward the end of the forecast at
HIB/BRD/HYR. LLWS is questionable at DLH and have left out due to
lower confidence.


DLH  67  46  73  56 /   0   0   0  30
INL  68  45  75  57 /   0   0   0  20
BRD  69  48  76  59 /   0   0   0  60
HYR  70  47  77  57 /   0   0   0  40
ASX  71  47  78  56 /   0   0   0  20


LS...Small Craft Advisory until 4 PM CDT this afternoon for LSZ140-



AVIATION...GSF is the U.S. government's official web portal to all federal, state and local government web resources and services.