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fxus64 ktsa 211729 

Area forecast discussion
National Weather Service Tulsa OK
1229 PM CDT Sat Sep 21 2019

concerning taf sites ktul/krvs/kbvo/kmlc/kxna/kfyv/kfsm/krog.
MVFR ceilings across northeast OK will gradually lift through the
afternoon with showers dissipating. While a few showers or storms
could re-develop later this afternoon, the more likely scenario is
for widespread showers and scattered thunderstorms to spread
across mainly northeast OK by early Sunday morning with
deteriorating flight conditions. Will also see areas of low clouds
with MVFR ceilings returning elsewhere for a short time around
sunrise Sunday. South winds will continue gusting around 20 kts
through the afternoon, and again by Sunday morning.


Previous discussion... /issued 1020 am CDT Sat Sep 21 2019/

cluster of ,moderate to occasionally heavy showers and embedded
thunderstorms associated with an mesoscale convective vortex in moist southwest flow
aloft continues to track along and north of I-44 in northeast OK.
Meanwhile a second feature is following close behind as has
resulted in enhanced area of showers now moving through okc
Metro. While this activity has shown some decreasing trend over
last couple of hours, it will keep rain chances relatively high
into early this afternoon, also mainly north of I-44. Temperatures
should be kept down a tad as a result though a late rally is
possible. Have updated the morning forecast to reflect these
trends, with the overall decrease in rain chances maintained for
the afternoon.

Previous discussion... /issued 631 am CDT Sat Sep 21 2019/


The discussion regarding the 12z taf forecast follows...

concerning taf sites ktul/krvs/kbvo/kmlc/kxna/kfyv/kfsm/krog.
Expect improving conditions by mid to late morning as cigs climb
from MVFR to VFR. There is a chance of showers this morning and
storms later in the day and this was reflected in the tafs with
tempo and thunderstorms in the vicinity respectively. Strong south winds expected again
today with gusts near 20 kts.


Previous discussion... /issued 318 am CDT Sat Sep 21 2019/

heavy rain potential over the next couple of days continues to be
the main forecast concern this morning, with the focus shifting
into mainly northeast Oklahoma.

An mesoscale convective vortex apparent in radar imagery over central Oklahoma early this
morning will continue to move slowly northeastward today and will
likely result in expanding showers and thunderstorms roughly along
and northwest of I-44 through the morning. This scenario is
depicted well in recent runs of the hrrr, with some potential also
extending into the afternoon hours. Tropical moisture remains
prevalent across the region, as the southwesterly flow aloft
continues to transport moisture from Hurricane Lorena into the
region. The 00z raobs from oun and Lamont show precipitable water
values near 2 inches within that plume, supporting some potential
for locally heavy rainfall. An overall lull in the activity should
occur for much of tonight, with coverage again likely to be expand
in advance of an approaching cold front during the day Sunday and
spreading southeastward with the front into Sunday night. The
heaviest rainfall is again expected to be across northeast
Oklahoma as the upper jet strengthens and makes its closest
approach. Depending on what happens this morning rain-wise in that
same area, some consideration may need to be given to a Flash
Flood Watch in the next 24 hours.

In addition to the heavy rain threat with both today's and
tomorrow's activity, a chance for isolated marginally severe
thunderstorms will exist, although the greater organized severe
weather potential should remain nearer the upper level support to
the north of the area.

Drier and cooler air will move in behind the front late Monday,
although this will be fairly short lived as a continued unsettled
pattern persists through the upcoming work week. Showers and
thunderstorms will again be likely Tuesday as an upper low in the
southwestern United States makes a slow eastward approach and
southwesterly flow once again develops aloft. Toward the middle to
latter part of the upcoming week, there are considerable model
differences regarding what will happen with that upper low. As
such, will largely stick with the fairly low pops offered by the
blended guidance given the high uncertainty on timing and areal


Preliminary point temps/pops...
tul 84 73 82 64 / 60 50 90 30
fsm 88 72 87 72 / 10 10 40 50
mlc 87 74 85 68 / 20 10 50 40
bvo 81 71 80 59 / 70 70 90 20
fyv 83 69 81 64 / 20 10 60 50
byv 85 71 83 64 / 30 10 60 50
mko 87 72 83 66 / 30 20 70 50
Mio 81 72 79 61 / 70 50 90 30
f10 87 72 83 66 / 30 30 70 40
hhw 89 71 88 71 / 10 10 20 30


Tsa watches/warnings/advisories...

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