Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KEAX 212309
AFDEAX

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
609 PM CDT THU JUL 21 2016

.Discussion...
Issued at 249 PM CDT THU JUL 21 2016

The excessive heat will continue to be primary concern through the
end of the week and likely into Sunday, before any kind of relief
occurs. But over the next 12 to 24 hours there is some potential for
a convective system or two to move into the area, possibly throwing
a wrench into the heat. Water vapor imagery shows a weak disturbance
moving through eastern Nebraska currently. Spotty but weak convection
has been persistent with this feature. Short-term models seem to be
resolving this feature and both the HRRR and the RAP track light
precipitation into northwestern Missouri tonight. While it`s possible
there could be some expansion of precipitation associated with this
weak wave, feel that with the forecast area being well within the
upper-level high, that that will suppress any convection that does
venture into the area. The other potential precipitation area may
come from a convective system that develops well north of the area
tonight and then tracks to the south or southeast into tomorrow. The
ECMWF and the GEM have this signal but seem to build it west, likely
along an outflow boundary, into the ridge. This seems unlikely to
occur given the strength of the upper high. So overall, have kept the
forecast dry.

Given the dry forecast, temperatures should be every bit as hot
tomorrow as they are today. We`ll have a very good chance at seeing
temperature reaching the century mark tomorrow afternoon. Also,
dewpoints have been slowly creeping downward from afternoon to
afternoon, probably because the recent higher ground moisture is
diminishing. So as temperatures have been increasing slightly each
day, dewpoints have been decreasing slightly each day. This give and
take has largely offset each other and our heat indices have climbed
slightly higher each day. A similar trend will occur Saturday and
once again we`ll likely see a few areas reach the century mark in
the forecast area. Heat indices will once again climb into the 105
to 110 range.

Models vary a bit with the timing of the front on Sunday. The ECMWF
is quicker with the front and thus is cooler on Sunday. The GFS is
slower and as a result has hotter temperatures through more of the
forecast area. Given the uncertainty, will keep the heat warning as
is, which currently drops the northern half of the forecast area on
Sunday. It`s possible, especially if the GFS is closer to reality,
that this area will need to be extended.

For next week, there is reasonable agreement with the models showing
the upper ridge retrograding to the west. This places the region
within weak northwesterly flow and it looks like there may be a
frontal boundary in the area. With the upper flow and a boundary in
the area, there appears to be a good chance for precipitation during
the early part of next work week.

&&

.Aviation...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 608 PM CDT THU JUL 21 2016

Still expecting VFR conditions to persist through the overnight hours
and into Friday. Marginal low level wind shear will be worth watching
with 500 to 1000 foot winds jumping into the 20 to 30 kt range.
Should surface winds go calm then LLWS concerns will increase
overnight. For now, with winds expected to remain 5 to 10 kts
overnight LLWS concerns are rather minimal.

&&

.EAX Watches/Warnings/Advisories...
KS...Excessive Heat Warning until 8 PM CDT Sunday for KSZ025-057-060-
     103>105.

     Excessive Heat Warning until 8 PM CDT Saturday for KSZ102.

MO...Excessive Heat Warning until 8 PM CDT Sunday for MOZ028>033-
     037>040-043>046-053-054.

     Excessive Heat Warning until 8 PM CDT Saturday for MOZ001>008-
     011>017-020>025.

&&

$$

Discussion...CDB
Aviation...Leighton



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.