Subj : MESO: Nws Weather Prediction Center College Park Md
To   : wx-storm@lists.illinois.edu
From : COD Weather Processor
Date : Mon Jul 03 2023 21:31:46

AWUS01 KWNH 032131
FFGMPD
MAZ000-NHZ000-RIZ000-VTZ000-CTZ000-NYZ000-PAZ000-040300-

Mesoscale Precipitation Discussion 0629
NWS Weather Prediction Center College Park MD
531 PM EDT Mon Jul 03 2023

Areas affected...Southeast NY...Southern New England...Ext.
Northeast PA...

Concerning...Heavy rainfall...Flash flooding possible

Valid 032130Z - 040300Z

SUMMARY...Scattered slow moving thunderstorms with capability of
repeating pose low end flash flooding risk through early overnight
period.

DISCUSSION...With a few hours left on the valid time of MPD 627
across S NY/N PA, stronger cells are starting to move out of the
eastern side into a more favorable convective environment;
however, a narrow band of enhanced instability is expected to
remain along the NE PA/S NY border as the surface low and
mid-level forcing wobbles eastward.   Five-hundred to 1000 J/kg of
CAPE will exist along this shear axis and in nearer proximity to
the upper-low, slightly slower and more directional difference in
steering flow should allow for slow cell motions with some
potential stationary nature at times along the axis.  This is
likely to continue just after nightfall once instability wanes and
capping increases.  Given rates of 1-1.5"/hr and similar totals to
2", isolated flash flooding remains a concern through 03z.

Further east, GOES-E Visible imagery shows increasing convective
vigor with a few additional stronger cells over the lower Hudson
Valley starting to move into CT. Persistent southwesterly low to
mid-level WAA has been providing moisture flux through this area
into Southern New England with total PWat values increasing from
1.75 toward 2" in the next few hours.  Additionally, fairly clear
skies has allowed for increasing instability up to 1500-2000 J/kg
across CT int RI.  As such, convection will likely strengthen and
broaden in coverage (both cells and downdraft area).  Forward
speeds are slow, but will start to slacken after 00z as a new
850mb pivot/low shifts toward the Hudson Valley, backing steering
flow increasing duration across southern New England for potential
for spots of 1.5-2.5" though 03z.  There is some uncertainty, but
initial band/round of cells and upstream advection of
moisture/low-level heating may allow for additional scattered
cells to form upstream and repeat through areas hit by the first
round.  As such and in combination with 1-3" that fell last
evening (across S New England)130, grounds may be prone to
scattered incidents of flash flooding tonight.=20=20

Gallina

....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!=
DZ3fjg!_tte8q0_aMoG1U2yarJtjENS7Hbtn6d9OMiPuZr8vigJIfPLE3ExgPeKLlmx53O5v_4q=
0stpwW9sRIxwwddEuAuk8d0$  for graphic product...

ATTN...WFO...ALY...BGM...BOX...GYX...OKX...

ATTN...RFC...MARFC...NERFC...NWC...

LAT...LON   43057274 42477155 42247128 41987118 41537136=20
            41347291 41157353 41107399 41287433 41537506=20
            41727634 42007659 42447635 42737465=20

=3D =3D =3D
To unsubscribe from WX-STORM and you already have a login, go to
https://lists.illinois.edu and use the "Unsubscribe" link.  Otherwise email
Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.14-Linux
 * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

.