Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 270842
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
342 AM CDT WED JUL 27 2016
.TODAY AND TONIGHT...Forecast Confidence Medium
Weak short wave energy helping to drive a small pocket of convection
in northern WI riding convergence along a weak surface trough/cool
front, with overall forcing for ascent aided by upper divergence in
the right rear quadrant of an upper jet max tracking north of the
upper Great Lakes. The MCS in Nebraska is riding on the nose of the
stronger low-level jet winds and 850 mb warm air advection, with the
eastern Dakotas/western Minnesota convection on the leading edge of
a weaker branch of the LLJ but within a pocket of better 700 mb RH
and a 700 mb speed max that tracks across northern WI later today.
All are within the better precipitable water channel arcing up and
around the surface to 925 mb ridging over the area that models show
will be slowly suppressed to the south with the approach of the
short wave, allowing the cold front/surface trough and associated
precipitation to sag towards and into southern WI later today.
Will slowly increase PoPs from north to south, beginning this
morning in the far north to acknowledge possibility in the GFS and
some of the hi-res models of a weak mid-level trough sagging into
the area. Best chances for showers and storms come with the passage
of the short wave trough and associated surface wave late this
afternoon and tonight. Will have the highest PoPs with the stronger
frontogenetic response across the northern half of the CWA tonight.
Will see high temperatures reached early in the afternoon with
increasing clouds and developing lake breeze halting the temp rise.
Looking at mid-upper 60s for overnight lows.
.THURSDAY AND FRIDAY...Forecast Confidence...Medium
A wave and weak surface front is expected to kick off showers and
storms on Thursday. Best chance is in the southwest toward the
Some moisture is expected to linger Friday, particulary toward the
southern forecast area. Overall though, not seeing much in the
way of forcing, so kept pops on the low end and confined to the
southern half of the forecast area.
With a good amount of clouds likely, especially Thursday,
expecting high temps within a couple degrees of normal in the
.SATURDAY THROUGH TUESDAY...Forecast Confidence...Medium
Looks mainly dry for the weekend under high pressure. Models
suggesting a weak wave may kick off a few storms Sat, so kept some
Could see a few storms via another weak wave or two early next
week, so maintained low end pops.
Should see near normal temps for the weekend, warming up a few
degrees above normal for Mon/Tue.
Again expect any patchy MVFR fog, with IFR in the Wisconsin River
Valley, to dissipate within a couple of hours after sunrise. Looking
for VFR conditions and light winds through most of the day, with
clouds and shower and thunderstorm chances increasing from north to
south during the day. Best chances for thunder will be tonight as a
surface low and cold front sag through the forecast area. Looking
for MVFR cigs/vsbys with the showers/storms.
Looking for light west winds to back around to the south ahead of
approaching surface low pressure and a trailing cold front. Bringing
a slight chance of showers and thunderstorms to the northern zones
this morning for the possibility of a weak trough sagging in from
the north, with the better chances coming tonight for the entire
nearshore. Winds turn northeast as the cold front drops through
tonight behind the low. Winds and waves will approach but remain
below small craft advisory levels Thursday and Thursday evening.
TODAY/TONIGHT AND AVIATION/MARINE...REM
Thursday THROUGH Tuesday...DDV