Area forecast discussion
National Weather Service Wichita Kansas
649 PM CDT Sat may 18 2013
Update...
issued at 649 PM CDT Sat may 18 2013
Update to the aviation section below for the 00z tafs.
&&
Short term...(this evening through tuesday)
issued at 247 PM CDT Sat may 18 2013
This evening and tonight...
the latest short term guidance suggests a better chance for
portions of central and especially south central Kansas being
affected by severe convection this evening as it evolves/moves
east off the dry-line further to the west. Strong to extreme
instability will be present at peak heating with initiation
expected just west of the forecast area by late afternoon or early
evening. This activity is expected to move east-northeast into at
least western portions of central and south central Kansas this
evening with shear profiles supportive of supercells and a few
tornadoes. Cap strength will be key in how far east this
convection can develop across the rest of central and south
central Kansas...though the NAM and GFS would suggest as far east
as the Turnpike through the early overnight hours. The prognosticated energy
helicity values below 3km and 1km suggests that a tornado
potential will exist even after dark up through midnight across south
central Kansas. While there is some negating factors with cap
strength and flow aloft for convective and supercell maintenance
into early tonight...the strong low level jet and rather
impressive instability does lead to keep this possibility open.
-Ked
Sunday...another round of significant severe weather is expected
across much of the area on Sunday-Sunday night. Much like this
afternoon...the dryline will be the primary focus for deep moist
convection during the middle to late afternoon hours but some
uncertainty remains in how far east the dryline mixes. The NAM is
the most aggressive and further east allowing low level flow to veer
to the southwest across much of south central Kansas which would
likely reduce the threat for tornadoes west of I-135 keeping the
greatest threat mainly east of the Wichita area across much of east
central and southeast Kansas. The GFS/European model (ecmwf) are less aggressive
mixing the dryline eastward while the GFS forecasts indicate a
retreating dryline Sunday evening supporting continued thunderstorm
development across portions of central/south central Kansas with
MUCAPE/hail growth region lapse rates supporting the threat for
large hail. The shear profiles continue to support supercells on
Sunday as a more robust h25 speed maximum ejects across the southern and
Central Plains. The deep layer shear becomes quite impressive with
0-8km bulk shear approaching 80 knots by 00z Monday. The potential for
supercells with very large hail and tornadoes will continue through
the evening hours across southeast Kansas.
Mon-Tue...will maintain afternoon probability of precipitation weighted over southeast
Kansas on Monday afternoon as a surface trough is prognosticated to remain
draped across the area and may provide a focus for deep moist
convection. Hard to rule out more severe weather but confidence
remains low at this time. More seasonable temperatures are expected
by Tuesday as the middle/upper trough continues to meander over the
northern plains and drier more seasonable air is advected across the
Central Plains states. -Mwm
Long term...(wednesday through saturday)
issued at 247 PM CDT Sat may 18 2013
A middle/upper ridge is prognosticated to return to the central and
Southern Plains in a pattern that may become favorable for
nocturnal thunderstorm activity and maintained probability of precipitation through much
of the period. Seasonably mild temperatures are expected with
highs in the upper 70s and lows in the 50s and 60s. -Mwm
&&
Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 649 PM CDT Sat may 18 2013
Anticipate scattered thunderstorms to affect the vicinity of all
tafs sites except kcnu through midnight. Some of the storms will
be severe...capable of damaging winds...large hail and isolated
tornadoes. Tornado threat may actually increase for a time this
evening as low-level jet strengthens. As storms run into a Stout
capping inversion...they should tend to weaken and decrease in
areal coverage after midnight...with activity possibly not even
making it to kcnu. In wake of storms...another round of low
ceilings/visibilities will be possible late tonight through Sunday morning.
Cold front/dryline will sweep east across the region
Sunday...sparking another round of strong to severe thunderstorms
generally along/east of kict-ksln Sun afternoon-evening.
West/northwest winds will spread east in wake of the
front...reaching the I-135 corridor around lunchtime.
Adk
&&
Preliminary point temps/pops...
Wichita-kict 68 86 60 81 / 60 50 60 30
Hutchinson 67 87 58 83 / 50 50 40 30
Newton 67 83 60 78 / 60 60 60 30
Eldorado 68 86 62 82 / 60 60 60 40
Winfield-kwld 69 86 63 81 / 60 60 60 40
Russell 64 82 52 79 / 60 40 20 20
Great Bend 64 82 53 79 / 60 40 20 20
Salina 68 85 58 80 / 40 50 40 20
McPherson 67 86 58 82 / 50 50 40 20
Coffeyville 70 87 66 82 / 20 60 70 60
Chanute 70 85 66 81 / 30 70 70 50
Iola 70 85 66 81 / 30 80 70 50
Parsons-kppf 70 86 66 81 / 30 70 70 60
&&
Ict watches/warnings/advisories...none.
&&
$$
