Area Forecast Discussion
Issued by NWS Topeka, KS
FXUS63 KTOP 061726
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1226 PM CDT Sun Jul 6 2014
...Update to aviation forecast discussion...
.SHORT TERM...(Today and Tonight)
Issued at 410 AM CDT SUN JUL 6 2014
A weak upper level trough over western MO and southeast KS will
shift east across southern MO and western AR during the morning
hours. The stronger ascent and weak isentropic lift currently across
the southeast counties will shift southeast as well bringing an end
to the isolated showers and thunderstorms after sunrise across
Coffey and Anderson Counties.
A weak cold front across northern NE and southern SD will move
southward through the day, into southern NE. The ECMWF shows a more
amplified upper level trough digging southeast across the northern
plains into the upper Midwest this afternoon. Scattered showers and
thunderstorms will develop across south central NE this afternoon
and a few may move into northern Republic and Washington Counties
after 600 PM.
Highs Today will reach the mid to upper 90s. Dewpoints will only mix
down into the upper 60s and lower 70s during the afternoon hours.
Thus, heat indices will rise into the 100 to 104 degrees.
Tonight, the weak front will stall out across the northern counties
of the CWA. The stronger ascent ahead of the H5 trough will
translate southeast across the northern plains into the the upper
Midwest. I placed slight chances for showers and thunderstorms
across the northern counties of the CWA. The surface based
thunderstorms, along the cold front, will probably weaken and
dissipate after sunset but isolated elevated thunderstorms may
redevelop through the night along the NE border and move east, as
stronger isentropic lift develops north of the surface front. Given
20 to 30 KTS of SFC to 6 km effective shear and MLCAPES of 1500-2000
J/KG along the NE border, some of the the stronger thunderstorms
late this afternoon and early this evening may produce small hail,
penny up to near quarters, gusty winds and brief heavy rainfall.
Lows Tonight will drop into the lower to mid 70s.
.LONG TERM...(Monday through Saturday)
Issued at 410 AM CDT SUN JUL 6 2014
Some isolated convection may be ongoing near the Nebraska border to
start the day on Monday...otherwise there should be a lull in
convection potential until later in the day along the Nebraska
border...although the better chances will remain north of the cwa
until later in the evening when a reinforcing push to the
front/outflow takes place as the southern portions of a possible MCS
or convection developing along the front move across the cwa from
northwest to southeast through the night. With the initial front
nearly stationary thru the day north of I 70...will see another hot
day in the southwest portions of the cwa with upper 90s to near 100
readings expected in the Minneapolis/Abilene vicinities with
generally the middle 90s common across the remainder of the county
warning area. Heat indices will vary from the upper 90s close to the
Nebraska border to the 100-103 degrees range from the Highway 24
corridor southward. The highest pops for this forecast will be
Monday night as the front/MCS moves through before drier air behind
the front/shortwave trough usher in drier and more stable conditions
into Tuesday night and Wednesday along with cooler temps. Highs both
days should be in the 80s.
As the front stalls to the south and winds become southeast...the
return flow will allow for moisture and warm air advection to
develop across the western portions of the cwa into Thursday which
will then spread north and eastward across the area through the
night resulting in an increase in thunderstorms chances once again.
Will increase highs Thursday back into the upper 80s and lower
90s...then the low to middle 90s all areas by Friday which will
persist into Saturday. Will keep low pops across the far
north/northeast portions of the cwa into Saturday with the approach
of the next front.
.AVIATION...(For the 18Z TAFs through 18Z Monday Afternoon)
Issued at 1218 PM CDT SUN JUL 6 2014
VFR expected at terminals as a weak frontal boundary approaches
from the northwest. Wind gusts subside late this afternoon as VRB
winds overnight veer to the southwest and increase just outside
current TAF period. For this evening, short term guidance holds
any developing TSRA to the north and east near the Nebraska