Area Forecast Discussion
Issued by NWS Topeka, KS

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 KTOP 291118
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
618 AM CDT Mon May 29 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 217 AM CDT Mon May 29 2017

Conditions for today and tonight look fairly tranquil, with a
couple of periods with potential for very light precip.

Northwest flow continues aloft with a short wave rotating around the
Lake Michigan upper low. This has pushed a weak cold front into the
Central Plains with a band of weak surface pressure falls (against
normal diurnal rises) across much of Nebraska and Iowa at 07Z. Cloud
cover is very sparse, but there is some mid cloud along the front,
and last few HRRR runs continue to bring very light scattered
showers across the area in the 9Z-13Z period. Have left sprinkle
mention with brief and high-based nature of this potential activity.
Low level temp trends show a bit of cooling occurring behind this
front for a slightly cooler day for much of the area. Mainly clear
skies dominate the afternoon through evening periods, but will need
to watch trends for the second potential precip period, late in the
night. The GFS and several of its ensemble members generate a band
of light precip across central Kansas. It is the most robust of the
operational models with modest mid-level isentropic upglide and
some saturation occurring in very weak instability aloft. Have gone
with only very small PoP for southwestern locations at this point.

.LONG TERM...(Tuesday through Sunday)
Issued at 217 AM CDT Mon May 29 2017

Tuesday brings the next chance for thunderstorms, as the LLJ
brings an area of showers and storms into central Kansas in the
overnight hours, while the larger scale upper trof swings another
lobe of energy over northeast Kansas in the afternoon. Enough CAPE
and directional shear that a few of these storms could be strong.
Area gets behind the shortwave in the flow for Wednesday which
relegates storm chances to our southwestern counties with the
northeast more likely dry. LLJ brings another overnight chance for
rain Wednesday evening and overnight.

Rain chances for Thursday through Sunday are more uncertain, with
an omega block over Canada, and weaker shortwaves moving into the
Central Plains states to the south. Flow in the column is weak
through Saturday, but ample instability for the potential for
storms to be strong should they develop. Better chances at this
time appear to be with the passage of the Friday trof and possible
front and shortwave on Saturday. Difficult to time individual
small scale systems in this regime, but pattern is overall unsettled
with chances for rain periodically through the extended.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 618 AM CDT Mon May 29 2017

Will watch radar trends for any VCSH very early in the forecast,
but latest trends suggest it will not be needed. Northwest winds
dominate again today. Light winds and mainly clear skies bring
some concern for BR formation late in the forecast, though
boundary layer appears quite dry. Too little confidence for
inclusion at this point.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...65
LONG TERM...67
AVIATION...65


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