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Area forecast discussion...updated 
National Weather Service Norman OK
832 PM CST Thursday Nov 26 2015

overall the forecast philosophy has not changed. Rain will
continue to affect the forecast area with heavy rain possible in some areas.
The cold front continues to move across the area with temperatures
dropping rapidly into the 30s and 40s after the passage of the
front. Some locations have reached the freezing mark in northwest OK but
much of the rain has moved out of this area for now. The freezing
line is expected to continue to slowly shift southeast overnight. Additional
rain is expected to move back into northwest parts of the forecast area later
tonight/early Friday so freezing rain/sleet is still possible
tonight into Friday. Overall the forecast looks good. Only changes
were to hourly grids to better represent the timing of the front.


Previous discussion... /issued 555 PM CST Thursday Nov 26 2015/

27/00z aviation disc below.

IFR/LIFR conditions will prevail most terminals through the
forecast period with widespread rain. Transition to freezing rain
and sleet will occur first across kgag/kwwr this evening and
spread south and eastward overnight and tomorrow. Switch to sleet
and possibly snow across kgag/kwwr but will leave mainly as freezing rain
and pl. Icing...some significant...appears likely from kgag/kwwr
down through kcsm and khbr through this forecast period. Strong
north winds will continue and compound ice accumulation effects.

Previous discussion... /issued 447 PM CST Thursday Nov 26 2015/

although the freezing line held in the western Oklahoma Panhandle
for a while... it is now making its way southeast through the
panhandles and Kansas. Sub-freezing temperatures will move into
Harper County this evening with the transition beginning to
freezing rain. The depth of the cold airmass suggests that there
will be a transition to sleet. Did not get too fancy with the
weather grids and used a combination of freezing rain and sleet
where winter precipitation is expected. Still have areas of
concern just north of the transition where surface temperatures
support ice and still closest to the northern edge of the primary
precipitation band... but also with the potential of another band moving
from the central Texas Panhandle into northwest Oklahoma on
Friday. So the risk of significant icing continues through the
area under the Ice Storm Warning. Will leave the Ice Storm Warning
as it is. For the Winter Storm Watch area... we are forecasting
the mix or transition to freezing rain and/or sleet into at least
the western portion of these counties tomorrow... but do not see
much winter weather potential until tomorrow afternoon. Have
converted the Winter Storm Watch to a Winter Weather Advisory and
will continue to monitor if the ice potential increases in this

Moderate to heavy rainfall is already occurring... especially in
southeast Oklahoma. But radar rainfall estimates are
underestimating the observed precipitation. Given the high
precipitable water content and the nature of the rain so far... we
are now changing the dual-pol precipitation algorithm to the tropical
setting. We are already getting videos or messages about flowing
water in streets in some areas and we have the added potential of
fallen Autumn Leaves to obstruct water flow and storm drains as
well. Biggest issue with the long duration event though may be
the creek and river flooding. Precipitation will persist through
Sunday... especially in the southeast.


Preliminary point temps/pops...
Oklahoma City OK 34 36 31 35 / 100 90 80 60
Hobart OK 32 34 29 33 / 90 90 80 60
Wichita Falls Texas 38 39 33 37 / 100 100 90 80
gage OK 25 27 22 31 / 70 80 60 50
Ponca City OK 33 35 31 35 / 90 90 70 50
Durant OK 45 48 34 40 / 100 100 90 90


Oun watches/warnings/advisories...
OK...Winter Weather Advisory from noon Friday to noon CST Saturday
for okz013-019-025-027>029-037-038.

Ice Storm Warning until noon CST Saturday for okz004>012-014>018-

Flash Flood Watch through Friday afternoon for okz025>032-

Flash Flood Watch through Saturday afternoon for okz043-047-048-

Texas...Winter Weather Advisory from noon Friday to noon CST Saturday
for txz085-087.

Ice Storm Warning until noon CST Saturday for txz083-084.

Flash Flood Watch through Friday afternoon for txz085-086-




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