000
FXUS63 KABR 161551
AFDABR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
1051 AM CDT SUN JUN 16 2013

.UPDATE...
MORNING INVERSION HAS RAPIDLY MIXED OUT...ALLOWING FOR
TEMPERATURES TO JUMP INTO THE MID 70S ALREADY.
SURPRISINGLY...DEWPOINTS HAVE REMAINED CONSISTENT...EITHER A
FEATURE OF MORE EFFECTIVE EVAPOTRANSPIRATION...ENTRAINMENT OF MID
LEVEL MOISTURE OR A COMBINATION OF THE TWO. MODELS STILL PUSH
HIGHER MIXED LAYER DEWPOINT AIRMASS INTO THE REGION...HOWEVER
REMAIN SKEPTICAL THAT WE WILL GO MUCH PAST 60F. THE COMBINATION OF
WEAK SHEAR AND INSTABILITY WILL BE A LIMITING FACTOR IN STRENGTH
OF ANY STORMS THAT FIRE BY EARLY/MID AFTERNOON AS BEST INSTABILITY
IS EVIDENT IN THE SEVERE STORMS JUST ACROSS THE MO. MESOSCALE
MODELS START STORMS OFF AROUND THE PERIPHERY OF THIS CONVECTIVE
CLUSTER...WITH CONVECTIVE INITIATION PROGRESSING TO THE NORTHEAST
CWA WITH A GENERAL SOUTHEAST MOTION...THOUGH ITS DIFFICULT TO
DISCERN A SPECIFIC FEATURE THAT THESE MODELS HAVE LATCHED ONTO AS
PER PREVIOUS DISCUSSION. HAVE ADJUSTED POP GRIDS AS SUCH...NO
OTHER CHANGES TO THE FORECAST OF SIGNIFICANCE.

&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TODAY THROUGH TUESDAY
THE THREAT OF SEVERE STORMS TODAY WILL BE THE MAIN FORECAST
CHALLENGE.

INCREASING MID LEVEL MOISTURE IS CURRENTLY MOVING NORTHWARD OVER
WESTERN SOUTH DAKOTA. WITH A WEST TO EAST FLOW ALOFT...THIS
MOISTURE GRADIENT SHOULD MOVE ACROSS THE EASTERN CWA THROUGH THE
DAY. THE NAM12 IS SUGGESTING MU-CAPE VALUES EXCEEDING 3000 J/KG
ALONG WITH 40 TO 50 KNOTS OF 0-6 KM BULK SHEAR BY THIS AFTERNOON.
CAPE IN THE HAIL GROWTH ZONE EXCEEDS 600 J/KG WHICH IS SUGGESTIVE
OF AT LEAST SEVERE HAIL. THAT SAID...THE LACK OF A SIGNIFICANT
FORCING MECHANISM MAY LIMIT THE THREAT OF SEVERE STORMS.

A MORE STABLE ENVIRONMENT WILL MOVE INTO THE REGION LATER
TONIGHT...WITH BASICALLY DRY CONDITIONS EXPECTED THROUGH THE REST
OF THE SHORT TERM PERIOD. THAT SAID...WEAK INSTABILITY ON THE
EASTERN SIDE OF A SURFACE HIGH PRESSURE MAY RESULT IN AFTERNOON
THUNDERSTORMS IN THE EXTREME NORTHEASTERN PORTION OF THE CWA ON
MONDAY.

.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY
UPPER LEVEL RIDGING WILL SETTLE IN OVER THE PLAINS TUESDAY
NIGHT...REMAINING DOMINANT THROUGH THURSDAY NIGHT BEFORE GETTING
PUSHED EAST BY A LOW PRESSURE SYSTEM TRACKING FROM THE PACIFIC
NORTHWEST TO SOUTH CENTRAL CANADA. A FEW SHORTWAVES WILL RIDE
THROUGH THE FLOW AND ACROSS THE STATE...THOUGH NONE OF THEM LOOK
TO BE TERRIBLY STRONG.

SURFACE HIGH PRESSURE WILL JUST BE EXITING TO THE EAST WHEN THE
PERIOD STARTS...WITH LOW PRESSURE APPROACHING FROM THE WEST. THE
SLOW MOVING SYSTEM WILL KEEP UNSETTLED CONDITIONS OVER THE
AREA...LOOKING TO JUST EXIT THE CWA AT THE VERY END OF THE
PERIOD. IT WILL BE TYPICAL OF AN UNSETTLED PERIOD WITH INSTABILITY
INCREASING EVERY AFTERNOON AND EVENING. THURSDAY AND FRIDAY LOOK
LIKE THE TWO DAYS WHERE THE MID LEVEL CAP MAY HINDER STORM
DEVELOPMENT...BUT AT THIS TIME...WILL JUST STICK CLOSE TO THE
ALLBLEND WHICH KEEPS A SCHC/CHC POP IN MAINLY FROM WEDNESDAY
NIGHT THROUGH THE END OF THE PERIOD.

WITH H85 TEMPERATURES IN THE UPPER TEENS TO MID 20S...WILL SEE
DAYTIME HIGHS IN THE LOWER TO MID 80S...AND OVERNIGHT LOWS IN THE
LOWER TO MID 60S.





&&

.AVIATION...
12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

VFR CONDITIONS WILL PREVAIL FOR THE MOST PART TODAY AND TONIGHT.
THERE IS A CHANCE FOR SOME SHOWER AND THUNDERSTORM ACTIVITY
BEGINNING ACROSS THE SOUTHWESTERN CWA THIS MORNING...THEN ACROSS
THE REST OF THE AREA DURING THE AFTERNOON HOURS. DID GO WITH A
VCTS MENTION AT KPIR WHERE THE CHANCES ARE BEST...WITH JUST A VCSH
MENTION AT THE OTHER THREE TAF SITES.








&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

$$
UPDATE...CONNELLY
SHORT TERM...SD
LONG TERM...PARKIN
AVIATION...PARKIN

WEATHER.GOV/ABERDEEN