Area Forecast Discussion
Issued by NWS Northern Indiana

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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

000
FXUS63 KIWX 161706
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
106 PM EDT Sun Jul 16 2017

.SYNOPSIS...
Issued at 100 PM EDT Sun Jul 16 2017

A weak cold front will continue to push through the region into
this evening. An isolated shower or thunderstorm may occur along
and southeast of Interstate 69, but severe weather is not
expected. High pressure will then build in to bring dry weather
and seasonably cool weather to start the week. Much warmer weather
can be expected by Wednesday as the low level flow becomes
southwest. Highs today and Monday will be mostly in the 70s, but
then approach 90 by the middle of the week.


&&

.SHORT TERM...(Today and Tonight)
Issued at 242 AM EDT Sun Jul 16 2017

Water vapor imagery depicting a series of well-defined
disturbances moving through NW flow from eastern Quebec...thru
southern Ontario...and back up into NE Manitoba. Surface analysis
has frontal wave over southern WI along slow moving cold front
extending across central lower MI back into IA. Regional radar
depicting remnant convection continuing to push south along WI/IL
border. Latest runs of HIRES guidance in line with going forecast
of a possible lingering shower or two making its way into far NW
CWA early this morning. NW flow becoming more amplified upstream
as upper jet dynamics coming onshore in Pacific NW has shifted
upper ridge axis from the Rockies toward the plains. Digging short
wave energy will combine with southward moving cold front to re-
ignite convection over our area this afternoon as favorable
diurnal timing will have increased instability over the eastern
portion of the CWA as ensemble means have CAPE values in excess of
1500J/kg. Deep layer moisture still lacking with this system but
antecedent boundary layer conditions should suffice to keep mid-
range chance POPs going. Low level flow non-existent and mid level
flow wont get this far south so weakly sheared environment does
not carry much of a severe threat. Lingering chances in far E/SE
CWA this evening as front continues to push through leading to dry
fcst by midnight.

&&

.LONG TERM...(Monday through Saturday)
Issued at 242 AM EDT Sun Jul 16 2017

Perfect mid-July weather to begin the long term period as
Canadian high pressure builds into the great lakes and midwest on
Monday. This will have temps running around 5deg below normal
Monday and Monday night with lower humidities. Temps bounce right
back to at or above normal as plains centered upper ridge expands
eastward. Enhanced and more zonal northern stream flow develops
north of upper ridge along US/Canadian border midweek. Surface
reflection in the form of slowly moving quasi-stationary boundary
will be focus for multiple rounds of convection across the
northern plains and upper midwest. Medium range models displaying
expected varying solutions as they have little skill at this range
with predominately mesoscale driven processes. Very weak signal
amongst the ensemble members for precip chances on Wednesday which
favors continued attempt to temporally trim back onset of POPs.
Also favor continuing to nudge maxT up a degree or two for
Wednesday toward ECMWF which has continued trend of further
eastward expansion of upper ridge which would yield temps 90 or
above over at least the southern half of the CWA. Chance POPs
continue days 5-7 as frontal boundary drifts southward into our
area.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon)
Issued at 106 PM EDT Sun Jul 16 2017

Front/wind shift has cleared KSBN and taking aim on KFWA. While
moisture remains in place behind the front, main focus of lift
will exist with the front, limiting chances for showers or storms.
Have removed any VC mention at KSBN and lower to VCSH at KFWA for
a few hours. As for flight conditions, some low clouds existing
behind the front but seem to be favoring locations west of both
sites for the time being. Will monitor trends, but not include in
18Z package. In addition, threat of low clouds/fog could
materialize later tonight into early Monday, but confidence low at
this time so will defer to later forecasts.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Beach Hazards Statement through late tonight for INZ003.

MI...Beach Hazards Statement through late tonight for MIZ077.

OH...NONE.
LM...Small Craft Advisory until 5 AM EDT Monday for LMZ043-046.

&&

$$

SYNOPSIS...Skipper/Fisher
SHORT TERM...JAL
LONG TERM...JAL
AVIATION...Fisher


Visit us at www.weather.gov/iwx

Follow us on Facebook...Twitter...and YouTube at:
www.facebook.com/NWSNorthernIndiana
www.twitter.com/nwsiwx
www.youtube.com/NWSNorthernIndiana



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