Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Milwaukee/Sullivan WI
237 am CDT Thursday Jul 30 2015
Today and tonight...forecast confidence high.
A very straight forward forecast this period. Persistence from
yesterday is the best approach. We remain in a very dry northwest
flow regime with deep mixing and breezy conditions expected again
this afternoon. Like yesterday...highs will be in the middle 80s and
dew points will mix out into the middle 40s to lower 50s. Westerly
winds will gust to 25 to 30 miles per hour at times. Given the low dew
points...temperatures tonight should still fall into the lower and middle 60s.
Friday - confidence...medium
swift northwest middle level flow continues with main emphasis from vorticity
maximum passing by to our north and northeast. Surface/850 trough
swings through later in the day into the early evening but
soundings look even less impressive than yesterday. Very dry with
little in the way of cape...so see no reason to go with any
mentionable probability of precipitation keeping them in the single digits. 925 temperatures show
around 20-22c with the GFS showing higher 925 temperatures which is
reflected with the higher MOS numbers as well. For now will steer
towards a blend especially given this dry westerly flow with decent
mixing can warm efficiently.
Saturday - confidence...medium
middle level flow remains from the northwest however not much to
latch onto. Surface/850 ridge axes nudge into the state. Some
950/925 warm air advection returns. Will keep dry forecast intact.
Saturday night and Sunday - confidence...medium
the arrival of a shortwave and a lower level trough axis will
enhance precipitation potential this period. Expecting a decent surge of
moisture ahead of the trough axis. There is reasonable consensus
on rain showers/thunderstorms and rain development and this could linger into Sunday
morning. Forecasts suggest some drying and potential subsidence
working in during the afternoon.
Sunday night and Monday - confidence...medium
appears a little stronger frontal boundary and approaching
stronger upper trough combine for yet another chance of rain showers/thunderstorms and rain
this period. Front shifts southeast Monday afternoon so best
chance looks to be in the morning.
Monday night through Tuesday night - confidence...medium
high pressure with a dry and cooler regime takes hold. Getting
some single digit celsius 850 temperatures from the 00z GFS with the
European model (ecmwf) only a smidge warmer.
Wednesday - confidence...medium
potential shortwave and renewed warm air advection brings some probability of precipitation back into
the forecast. Confidence at this point in anything siggy here not
great though as 850/925 baroclinicity proggd to remain further
south and southwest of the area. 00z European model (ecmwf) shows stronger
convective signal tied to this boundary further south with only a
glancing shot here. For now will go with the superblend probability of precipitation.
Aviation/12z tafs/...VFR conditions expected through the taf
period. Similar to yesterday...westerly winds will be breezy with
speeds in the 15 to 25kt range from late morning through the
afternoon. Winds will diminish rapidly toward sunset.
Marine...a Small Craft Advisory is in effect for breezy west winds
of 15 to 25 knots from late morning through about 7 PM this
Lm...Small Craft Advisory from 11 am this morning to 7 PM CDT this
evening for lmz643>646.
Today/tonight and aviation/marine...Davis
Friday through Wednesday...collar