Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI
FXUS63 KMKX 251539
Area Forecast Discussion
National Weather Service Milwaukee/Sullivan WI
1039 AM CDT THU AUG 25 2016
Cold front is pushing out of the area this morning, taking much of
the cloud cover with it. However, there is a complex of weakening
thunderstorms over the MO/IA/NE/KS area that is moving to the
northeast. These storms are roughly in the right entrance region of
the jet, the that is the only forcing evident for these storms. Any
CAPE available for these storms is to the southeast of the cold
front, well away from WI.
There is no concern for these storms reaching WI, but it appears
that some of the mid and upper level clouds with these storms may be
blown into our area in the late morning and persist into the
afternoon. However, there is no forcing or instability over WI, so
am not confident that these clouds will hold together all the way
through our CWA.
To account for these clouds, have upped the sky coverage over
that time frame. Models are not resolving these clouds well, so I
will likely be dropping afternoon temperatures somewhat. These
changes will be tempered given the low confidence in the clouds
making it through our CWA.
VFR conditions should e in place through the TAF period. That
said, overcast mid clouds from a thunderstorm complex over SW IA
are moving towards WI. Not confident that these clouds will remain
overcast as they approach the area, but should see at least
scattered, if not broken, mid clouds late this morning and into
Relatively strong NW flow behind the cold front and warm lake
waters should keep much of a lake breeze from forming, though some
of the high resolution guidance does show winds along the lake
swinging to more of a southerly direction this afternoon. Have
included this wind shift in the lakeshore TAF sites.
Light winds and low wave heights expected into Friday,
with a lake breeze each afternoon. The next chance for showers and
thunderstorms will be late Friday night.
.PREV DISCUSSION... /Issued 403 AM CDT THU AUG 25 2016/
TODAY AND TONIGHT...Forecast confidence...High.
Scattered showers and isolated tstorms will continue to stream newd
early this morning from nw IL to se WI. The showers are along a slow
moving cold front with a vorticity maximum aloft. Some heavy
rainfall rates will occur but probably not as heavy as earlier this
morning in the far srn counties. Expect the showers to end around
15z in far se WI. Otherwise dewpoints will lower into the upper 50s
to lower 60s with little to no cumulus this afternoon although some
cirrus is expected. Thus high temps will be in the lower 80s. Weak
cold advection will then prevail tonight with high pressure moving
from the northern Great Plains to the Upper MS River Valley. Lows
will range from the middle 50s nw CWA to the lower 60s in far se WI.
High pressure will likely bring pleasant weather to southern
Wisconsin on Friday. Will probably see mid/high level clouds
increase from the southwest during the day, but the day will at
least start out with a good amount of sunshine. High temps will be
comfortable in the mid/upper 70s.
FRIDAY EVENING THROUGH SATURDAY...Forecast Confidence...Medium
Deeper surge of moisture will push in from the southwest Friday
evening and overnight. Will see decent warm advection too as low
level jet increases over southern Wisconsin. Bumped pops up quite
a bit for this period (especially after midnight) with models in
decent agreement with a shortwave lifting through.
Showers/storms will then be likely across southern Wisconsin
Saturday ahead of an approaching trough. Precip chances will
linger into Sat night as the trough moves through. Could see some
locally heavy rainfall, with precipitable water values up around
Should see near normal temps on Saturday.
SUNDAY THROUGH WEDNESDAY...Forecast confidence...Medium
Surface high pressure will be in place for most of the time Sunday
through Wednesday. The overall upper level pattern will be ridging
during this time period, so warm temps are expected for the first
half of next week. Kept it mainly dry through Wednesday, though
have some low pops at times as a weak wave or two may move through
the northern periphery of the ridge.
AVIATION/12Z TAFS/...IFR to MVFR cigs will occur at times through
15z over the se WI TAF sites as the cold front moves very slowly
through the region. Scattered showers and isolated tstorms will
accompany the front and greatly reduce cigs and vsbys during heavy
rainfall. Otherwise little to no cumulus is expected for the
afternoon with mo clear skies tonight.
MARINE...Light winds and low wave heights for today and Fri. A
lake breeze is expected each afternoon. There could be brief periods
of fog this morning south of North Point Lighthouse due to the
humidity and rainfall.
TODAY/TONIGHT AND AVIATION/MARINE...Gehring
Friday THROUGH Wednesday...DDV