Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 06/09/22
Area Forecast Discussion
National Weather Service Indianapolis IN
1036 PM EDT Wed Jun 8 2022
...Updated Aviation Discussion...
.Forecast Update...
Issued at 1000 PM EDT Wed Jun 8 2022
Clearing continues, and post-frontal northwesterly winds have
decreased and will remain light tonight. They should stay up
enough for sufficient mixing to mostly limit fog development. The
forecast is in good shape and only minor adjustments were made
based on observational trends.
&&
.Short Term...(This evening through Thursday night)
Issued at 301 PM EDT Wed Jun 8 2022
Main concerns for this evening:
-Potential for severe weather through 02Z
-Brief heavy downpours with convective elements
-Frontal passage will bring west/northwest flow overnight
Current Synoptic Setup: Satellite imagery showing several
interesting features across Central Indiana, starting with the mid-
lvl clouds sliding east and showing some anti-cyclonic turning with
some vertical growth in this area. Further south the cumulus field
has grown in its footprint, but equally beginning to show some
vertical growth as well with convergence of the cumulus layers. This
cumulus layer is also found in the area where surface dewpoints have
continued to rise with the moist surface conditions, as TD`s near 70
degrees. Some backing in the surface winds are also noted between I-
70 and I-64 in Indiana. Further south across Northern KY the
atmosphere has been further destabilized, with surface flow more
backed to the south. ACARS data the last few hours across KIND have
continued to show a dry layer aloft; however, it has been steadily
moistening through the profile. That being said it is possible that
with some convective elements developing in this dry layer over
Central IN that some stronger updrafts could present larger hail
stones.
The jet exit region continues to be further upstream across IA, but
has been slowly pivoting southeast as the 850mb trough progress`s
east. The deep layer shear has been rather robust overhead as well,
with values hovering in the 50-60kts range. This coupled with some
low-level helicity and boundaries proximity has introduced the
potential that upscale growth to convective elements could begin to
demonstrate rotating updrafts, thus we have tornado watch issued
until 2Z this evening. Latest surface obs also support this with an
axis of higher helicity centered along and south of IND to BMG.
Based on forward propagation, it would indicate the timing of
convection pushing east for Central IN would likely occur well
before this current ending.
Later Tonight through Thursday: 850mb trough axis continues to push
east overnight ushering in the frontal boundary. This will bring
much drier air into the lower levels and an end to precip as anti-
cyclonic flow brings diffluent flow through the lower-levels. Temps
should steadily fall into the mid 50s overnight, and with subsidence
eroding some of the low-level moisture expect a gradual clearing to
cloud cover overnight but not completely clear skies. Thur should
provide considerable sunshine with diffluent flow from ridging
overhead. Temps will rebound into the upper 70s with some fair-wx
cumulus progged or more diurnally driven.
&&
.Long Term...(Friday through Wednesday)
Issued at 301 PM EDT Wed Jun 8 2022
Friday-Friday night will feature rain chances returning yet again as
a seasonably strong H500 wave crosses the region during the day. A
relatively weak open-wave low will be the surface reflection...with
corresponding fronts aligned west-to-east across the Mid-West.
Forcing aloft should lead generally light to moderate rainfall...
with isolated thunder possible with the wave`s timing matching
diurnal heating well. Potential for stronger thunderstorms appears
limited with near-zero instability despite adequate shear throughout
the profile. Weak surface gradients will promote southwesterly
winds less than 10 mph, which is expected to provide only modest
dewpoints in the 50s...and slightly below normal temperatures
ranging from highs generally in the mid-70s to lows in the mid-50s.
Saturday-Sunday should be mainly dry as a couple more weak, quickly-
passing waves flow over the southern Great Lakes amid somewhat
strong upper-level northwest flow. Isolated showers will be possible
at times, generally across north-central and northeastern zones
which will be closer to the passing vort maxs. Slightly lower
heights and partly sunny skies will combine to bring near normal
temperatures.
Monday-Wednesday will favor a slowly-advancing warm frontal zone
that will lead to the subtropical warm sector building into the CWA
underneath an amplifying mid-level ridge. Rain will be most likely
Monday through early Tuesday...and although forcing aloft may be
marginal, precipitable water values quickly rebounding into the 1.50-
2.00 inch range should produce numerous showers along the boundary.
At a glance any thunderstorm potential should be guided by another
ample-shear, low-instability set-up, although these details will be
refined with future runs. Appears the late Tuesday-Wednesday
timeframe will have deep southwesterly flow...around a strong trough
lifting from the central US into a larger south-central Canada
cyclone...that will promote noticeably warmer conditions. Some
uncertainty surrounds the curvature of the broad central US upper
ridge into next week...as the troughs combining near the Great Lakes
may suppress heights over the Mid-West. Temperatures will likely be
above normal, although intensity of heat will depend on how much any
northern troughiness slides east or sags southward toward the
region. Appears greater likelihood for well above normal readings
across southern counties...with low chances for precipitation as the
pattern would not support adequate forcing along any approaching
weak boundaries.
The normal max/min for the Indianapolis Area through the long term
period is 81/62.
&&
.Aviation...(06Z TAF Issuance)
Issued at 1036 PM EDT Wed Jun 8 2022
IMPACTS:
* MVFR stratus possible later this evening through early morning.
DISCUSSION:
Confidence in timing and duration of MVFR stratus is somewhat low.
Observations show low stratus upstream across northern Indiana, and
models show this moving southward later tonight. Timing in the TAFs
remains rather broad and amendments may be needed. A return to VFR
conditions is expected by late morning and light northwesterly winds
will prevail.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
Update...BRB
Short Term...Beach
Long Term...AM
Aviation...BRB