Area forecast discussion
National Weather Service Dodge City Kansas
621 PM CDT Tuesday Jun 18 2013
..updated aviation discussion...
Synopsis...
issued at 1000 am CDT Tuesday Jun 18 2013
The 18.12z 250 hpa radiosonde observation map showed two jet streak across the Continental U.S..
one 95 knots streak across the Pacific northwest and another 115 knots streak
across the northeast. Flow across the Central Plains was westerly around
60 knots. At 500 hpa, a large 550 dm cyclone was located just offshore
of Washington state. Fairly cold middle level temperatures around -24 degree
c were associated with said feature. Downstream, a few shortwave troughs
were moving across the upper Midwest and into the Ohio River valley.
Another deep cyclone was located across southeast Canada with middle level temperatures
around -28 degree c. At 700 hpa, less of an upslope flow pattern was noted
at kddc. Temperatures were fairly unchanged from yesterdays 12z flight...still
@ 8 degree c. Slight cooling was noted at 850 hpa @ kddc with the observed
value at 18 degree c instead of 20 degree c. Again, less of an upslope flow
pattern was noted in the wind field. At the sfc, a stationary front
was noted across Colorado extending southward to the Texas Panhandle.
Tropical Depression Two was located @ 17.9n 90.0w @ 15z.
&&
Short term...(this evening through wednesday)
issued at 100 PM CDT Tuesday Jun 18 2013
Tonight:
Kddc WSR-88D indicating returned power this afternoon. This activity
is in response to a weak wave moving out of northwest Kansas and surface convergence.
Showers and thunderstorms will continue this afternoon and evening and
will eventually spread east or southeast. A few severe strong or severe
storms are possible, however, shear is pretty weak. Overnight lows will
be slightly higher as dewpoints are a degree or two higher...middle 60s.
Tomorrow:
Early convection will still be possible Wednesday morning along a surface
convergence line and weak upper level wave moving across the region.
Have precipitation probability percentage points peaking at 18z and
then tapering through the rest of the afternoon as the wave and resultant
support moves east. Highs tomorrow will be in the middle 80s to middle 90s.
Long term...(wednesday night through tuesday)
issued at 1243 PM CDT Tuesday Jun 18 2013
Wednesday night through friday:
a return to hot weather is expected for late in the week as very
warm 850-700mb downslope-warmed air advects east into western
Kansas. While organized thunderstorm activity is not
anticipated...the Wednesday night period will have to be watched
mainly across central and south-central Kansas as a shortwave
disturbance moves across Kansas (subtropical in nature as the main
polar jet trough will be well off to the northwest). The global
models seem to be fairly persistent in showing a convective quantitative precipitation forecast
signal rolling east across Kansas Wednesday evening which seems to
be tied to warm frontogenesis in the 800-700mb layer. Any convective
threat should be early in the evening across mainly the far eastern
counties (generally east of Highway 183). The dryline will push east
a bit on Thursday thanks to increased southwesterly momentum in the
850-700mb layer. Along and west of the dryline...critical fire
weather conditions will likely develop as surface relative humidity plummets to the
Lower-Middle teens percent. Along the dryline both Thursday and
Friday...an isolated thunderstorm cannot be ruled out as convective
temperature is reached and a continued rather moist airmass east of
the dryline both Thursday and Friday evenings (dewpoints in the
upper 50s to lower 60s). A subtropical upper tropospheric jet 45-50
knots from New Mexico into western Kansas may provide enough deep
tropospheric ascent and shear for a few severe storms...but coverage
at this time looks rather sparse... so will only be going with
slight chance probability of precipitation across the far southwestern Kansas counties for
now.
Saturday through tuesday:
during this time frame...a large upper low across the Pacific
northwest region/adjacent northern rockies will lift northeast and
become absorbed in the polar jet stream flow in southern Canada. A
subtropical (yet rather weak) jet will continue from Arizona through
New Mexico into the Central High plains. This subtropical jet will
eventually weaken as middle level anticyclogenesis begins across the
southern High Plains. This ridge-building will mark the beginning of
the traditional Summer pattern as a 595+ decameter high at 500mb
will eventually become a dominant feature across the
central/south-central Continental U.S.. a surface front will likely approach
western Kansas on Sunday...however this front should dissolve late
Sunday/Sunday night (although not before some thunderstorm chances
along the front). Highs each day in the middle to upper 90s seem
likely...with the persistent 100-degree heat expected across
northwest Kansas and into southwestern Nebraska.
&&
Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 619 PM CDT Tuesday Jun 18 2013
Strong to severe thunderstorms near Hays will move south and are
expected to weaken through sunset. At this time it appears these
thunderstorms will approach the Dodge City Airport between 0230z and
04z if these storms hold together. Another chance of thunderstorms will
then be possible at all taf sites between 09z and 12z as an upper
level trough exits The Rockies and crosses the Central High
plains. Model soundings suggest that cloud bases will be above
4000 feet so VFR conditions are expected through early Wednesday
morning. Prevailing winds overnight are will be south/southeast at
10 to 15 knots.
&&
Preliminary point temps/pops...
ddc 64 88 67 99 / 30 40 20 10
gck 63 90 66 101 / 30 40 10 10
eha 63 93 66 102 / 30 20 10 10
lbl 63 92 67 102 / 30 30 10 10
hys 66 86 67 94 / 30 40 20 10
p28 67 87 68 95 / 30 30 30 10
&&
Ddc watches/warnings/advisories...
none.
&&
$$
Synopsis...Sugden
short term...Sugden
long term...umscheid
aviation...burgert
