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fxus64 koun 201941 

Area forecast discussion
National Weather Service Norman OK
241 PM CDT sun Oct 20 2019

upper low will move across NE/South Dakota the rest of this afternoon into
tonight. An associated cold front, that is currently in the
panhandles about to move into northwest OK, will move across the area.
Meanwhile, moisture will continue to spread northward ahead of the
front, especially into southeast parts of the fa where dewpoints in the 60s
are likely. How much moisture is able to spread into the area, could
be a factor, in potential severe weather this evening/overnight. But
first, convection is expected to develop this evening, mainly after
7 PM, along and ahead of the cold front as it moves into better
moisture in eastern portions of the fa. Thunderstorms will remain
possible into the overnight hours as the cold front continues to
move across the region with rain ending early Monday as the front
exits the area. The highest chances will be in southeast portions of the fa
where the better moisture is expected to be.

Now on to the severe potential, instability and shear are expected
to be sufficient for severe storms to be possible in parts of the
area, especially in southeast portions of the fa. Large hail, damaging
winds, and tornadoes are all possible. There are some uncertainties
for this evening, including as previously mentioned, how much
moisture will be able to move into the area and whether the storms
can become surface based. If storms can become surface based, the
strengthening of a strong low level jet this evening will increase shear and
could lead to some tornadoes, especially if storms remain as
supercells and don't quickly become a line of storms, although in
that case qlcs tornados could be a possibility. The timing could
also be problematic and dangerous with the fast moving storms, any
tornadoes, likely occurring after dark.

Breezy northwest winds are expected behind the front Monday. The breezy
winds and low rhs that are expected could lead to elevated fire
weather conditions Monday afternoon.

Models show the next system will affect the region towards the end
of the week, although there continues to be significant differences
between models and sometimes from run to run as to how the upper
system will evolve. The GFS keeps the system as a progressive trough
that quickly moves across the region. Meanwhile, the Canadian and
European model (ecmwf) has a closed low that develops and slowly moves across the
Southern Plains. Whether the system stays an open wave or a slow
moving closed low will have an impact, especially on pops and how
long precip will be possible. The one thing all the models seem to
agree on is that an associated cold front will move across the
region Wednesday night/Thursday bringing some colder air to the


Preliminary point temps/pops...
Oklahoma City OK 48 69 41 71 / 40 0 0 0
Hobart OK 46 72 39 73 / 10 0 0 0
Wichita Falls Texas 50 74 43 75 / 40 0 0 0
gage OK 41 68 35 71 / 10 0 0 0
Ponca City OK 47 67 38 67 / 20 0 0 0
Durant OK 53 74 44 74 / 90 0 0 0


Oun watches/warnings/advisories...

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