Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Milwaukee/Sullivan WI
346 am CDT Wednesday Jul 23 2014
Today and tonight...forecast confidence high.
Cooler and drier air moving in with high pressure as region comes
under northwesterly upper level flow with deepening upper trough to the east.
Sheared vorticity...associated with 80 knots 250 mb jet maximum currently
cresting upper ridge centered over the inter-mountain region...will
pass to the west today. Second weak short wave trough drops through
this evening...but little to no moisture. Will see some diurnal
cumulus develop by afternoon with steep low level lapse
rates...dissipating by evening.
Some differences among models with how cool 850 mb and 925 mb
temperatures fall with cold air advection. A blended solution brings
highs into the upper 70s in the west...with northeast winds off the
Cool Lake holding readings in the upper 60s to lower 70s in the
eastern third...with middle 70s in between.
Winds lower tonight and skies clear allowing lows in the lower to
middle 50s...through slightly warmer along the lake. Expect patchy
fog...with some local areas of fog possible in the river valleys and
low-lying rural areas.
High pressure will bring another pleasant day Thursday. Plenty of
sunshine is expected to go along with highs in the 70s.
Kept some probability of precipitation mainly in the west Thursday night...as increasing
warm advection on the nose of a strong low level jet will likely
kick off a round of showers/storms in the region.
Friday through Sunday...forecast confidence...medium
A series of shortwaves are expected to bring shower/storm chances
to southern Wisconsin at times Friday through the weekend. Models
still have some details to work out...so left chance probability of precipitation through
the weekend. Trended probability of precipitation a bit cooler Friday per lower 925 mb temperatures
and expected clouds/precip. Still should be in the 70s though
Friday...with highs back around 80 for Sat/sun.
Monday and Tuesday...forecast confidence...medium
It looks like there will be less available moisture early next
week...but still went with some low probability of precipitation Monday and Tuesday as
models are advertising a couple weak waves. Temperatures will likely be
comfortably back into the 70s both days.
VFR conditions expected with diurnal cumulus developing by
afternoon...though staying at VFR levels around 5k feet. Gusty
northeast winds in the east will slowly lower during the afternoon.
Clear skies and light winds overnight bring the potential for patchy
fog...but MOS guidance not showing fog at any of the taf sites so
will leave out for now.
Small Craft Advisory remains in effect for high waves with
persistent northeast winds through the day. Winds slowly ease during
the afternoon with waves slower to subside so will keep current end
time for advisory...with the northern-most zone ending at 00z and
the remainder at 06z.
Sheboygan...Ozaukee...Milwaukee...Racine and Kenosha counties
will be in a high risk of swimming hazards today...with all but
Sheboygan County remaining in a high risk into the evening...due
to high waves with persistent northeast winds. Winds slowly ease
during the afternoon...but waves will be slower to subside until
this evening. The onshore fetch and high waves will cause
dangerous currents along the shore...especially around piers and
WI...beach hazards statement through late tonight for wiz060-066-071-
Beach hazards statement through this evening for wiz052.
Lm...Small Craft Advisory until 1 am CDT Thursday for lmz644>646.
Small Craft Advisory until 7 PM CDT this evening for lmz643.
Today/tonight and aviation/marine/beaches...rem
Thursday through Tuesday...ddv