Scientific Forecaster Discussion
fxus63 kind 262048
Area forecast discussion
National Weather Service Indianapolis in
448 PM EDT Wed Jun 26 2019
the aviation section has been updated below.
issued at 232 PM EDT Wed Jun 26 2019
High pressure in place over southern Appalachia will provide
warm...humid...seasonable Summer weather for central Indiana for
the rest of the work week. Most locations will stay dry through
Friday...however a few very isolated showers and storms cannot be
ruled out due to the warm and humid air mass in place.
This weather pattern looks to continue into the weekend. A more
organized system will arrive early next work week, bringing better
chances for rain.
Near term /tonight/...
Issued at 232 PM EDT Wed Jun 26 2019
Surface analysis this afternoon shows high pressure in place from
West Virginia to Georgia. Warm and humid southwest flow was in
place across Indiana. Dew points were in the mid to upper 60s.
Goes16 shows a field of cumulus across the SW parts of the forecast
area. Satellite shows an mesoscale convective vortex over SW MO...producing a few showers.
Meanwhile aloft...ridging was in place across the plains states.
The ridge is expected to strengthen overnight and relatively weak
flow will remain in place aloft. The models suggest that the mesoscale convective vortex
will make minimal progress southeast...while a weak short wave arrives
from the northwest. Forecast soundings show steep lapse rates with
attainable convective temperatures for a few hours. However deep
moisture and organized forcing does not appear available. Hrrr
shows a band of showers moving into the SW tonight...but that
seems associated with mesoscale convective vortex which and it will be unlikely that it
makes that quickly of an approach. Thus will keep some very
minimal chances for precip tonight for the renegade shower...but
most areas will look to remain dry. Confidence for rain is low.
Given the warm and humid air pass in place...will trend temps at
or above the nbm blends.
Short term /Thursday through Saturday/...
Issued at 232 PM EDT Wed Jun 26 2019
Models suggest that strong ridging will build across the
Mississippi Valley through Saturday...allowing weak northwest flow to
persist aloft over Indiana. Within the flow aloft the models show
a few weak...unorganized short waves passing toward Indiana. Time
heights show Manly only lower level through the period with
subsidence in place on Thursday through late Friday night.
Forecast soundings again show limited deep moisture and the
primary form of available lift appears to be summertime daily
heating. Thus again...confidence for organized showers during
this time is low. Again...most areas should remain dry...but an
isolated diurnal shower or storm cannot be ruled out. Will
probably use very low pops. Given the warm air mass in
place...will trend highs and lows at or above the nbm blends.
Long term /Saturday night through Wednesday/...
issued at 300 PM EDT Wed Jun 26 2019
Models and ensembles generally keep the forecast area under of
stagnant ridge of high pressure, typical for this time of year. This
supports mainly dry weather with above normal temperatures and high
humidity. However, there is enough dip in the westerlies to support
chance pops next Tuesday and Wednesday per the blend.
Aviation /discussion for the 26/21z taf update/...
Issued at 445 PM EDT Wed Jun 26 2019
good confidence in VFR conditions through the period per the GFS
lamp and sref and as high pressure is in place. Would not rule out a
brief thunderstorm 18z-02z as instability will become strong.
Winds will be southwest near 10 knots and become calm or light and
variable after 02z.