FXUS63 KOAX 020810
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
310 AM CDT THU JUN 2 2011
.DISCUSSION...
CONVECTION HAS FOCUSED MAINLY IN KS IN THE EARLY MORNING HOURS
TODAY. SUBJECTIVE 00Z UPPER AIR ANALYSIS INDICATES UPPER-LEVEL LOW
COMING ASHORE IN THE WESTERN US...WITH TROUGHING DEEPENING IN THE
WEST. SECOND LOW WAS CENTERED IN EASTERN HUDSON BAY...WITH RIDGING
BETWEEN ACROSS THE CENTRAL US. 850MB MOISTURE HAD RETURNED INTO THE
CENTRAL US...WITH NOSE OF 8C+ DEWPOINTS EXTENDING INTO WESTERN
SD...AND A MAX OF 16C AT KLBF. SURFACE LOW AT 07Z WAS CENTERED WELL
WEST...IN SOUTHEAST MT/NORTHERN WY...WITH INCREASING SURFACE
PRESSURE GRADIENT ACROSS THE PLAINS. PROFILERS AT 07Z HAD HAD
REACHED 40KT IN KS...FEEDING INTO AN MCS MOVING ACROSS NORTHEAST KS.
MAIN FORECAST CONCERNS INCLUDE PROGRESS OF NOCTURNAL CONVECTION THIS
MORNING THROUGH THE FRINGES OF THE CWA...POTENTIAL FOR CONVECTIVE
DEVELOPMENT TO AFFECT THE AREA TONIGHT...AND CONTINUED /MAINLY
NOCTURNAL/ CONVECTIVE POTENTIAL THROUGH THE WEEKEND. AS SHORT-RANGE
MODELS CONTINUE TO STRUGGLE WITH ONGOING CONVECTION...AM RELYING ON
OBSERVATIONAL INFORMATION FOR CONVECTIVE FORECAST THROUGH THIS
MORNING. BELIEVE KS MCS IS THE FOCUS FOR THE EARLY MORNING
HOURS...WITH A FEW LINGERING WIDELY SCATTERED SHRA/TSRA FURTHER
NORTH IN NEB/WRN IA. HAVE INCREASED POPS IN THE SOUTH/SOUTHEAST
THIS MORNING FOR LINGERING SHOWERS/ISOLATED THUNDER ON THE NORTHERN
FRINGE OF THE MCS...BUT BELIEVE PRECIP SHOULD CLEAR BY AROUND
MID-MORNING AS LOW-LEVEL JET WEAKENS AND VEERS.
CWA SHOULD REMAIN DRY THROUGH THE DAY TODAY BEHIND THE MORNING
MCS...WITH SUBSIDENCE IN ITS WAKE AS WELL AS INCREASING 700MB TEMPS
THROUGH THE DAY. TIGHT PRESSURE GRADIENT SHOULD ALLOW GUSTY
WINDS...BUT HAVE KEPT WINDS BELOW ADVISORY CRITERIA.
NONETHELESS...STRONG MIXING SHOULD PUSH TEMPS INTO THE UPPER 80S
EAST/LOWER 90S WEST. AFTERNOON CONVECTION APPEARS TO BE MOST LIKELY
WELL TO THE NORTH IN ND/NORTHERN SD...CLOSER TO THE SURFACE LOW AND
UPPER-LEVEL LOW...AND POSSIBLY IN WESTERN KS AHEAD OF A SECONDARY
LOW. CWA SHOULD BE DRY BETWEEN THOSE AREAS. WITH SOUTHWESTERLY
850MB WINDS BRINGING DRIER 850MB DEWPOINTS ACROSS THE
PLAINS...SUPPORT FOR NOCTURNAL CONVECTION TO DEVELOP FROM THE KS
CONVECTION SEEMS WEAK...AND HAVE KEPT DRY FORECAST THROUGH THE NIGHT.
SURFACE AND MID-LEVEL FRONT BOTH ARE PROGGED TO DESCEND INTO THE CWA
ON FRIDAY. TEMPS ON THE COOL SIDE SHOULD STAY IN THE LOWER
80S...WHILE TEMPS ON THE WARM SIDE COULD STILL RISE TO NEAR 90.
THINK AREA WILL BE TOO CAPPED FOR DAYTIME CONVECTION AS 700MB TEMPS
OF 12-14C PERSIST AHEAD OF THE FRONT...BUT INCREASING LOW-LEVEL JET
IMPINGING ON THE MID-LEVEL BOUNDARY SHOULD ALLOW SHRA/TSRA TO
DEVELOP OVERNIGHT...WEAKENING AND MOVING OUT OF THE AREA IN THE
MORNING HOURS. BOUNDARY IS PROGGED TO LINGER IN OR NEAR SOUTHERN
NEB/NORTHERN MO ON SATURDAY...AND WITH COOLING MID-LEVEL TEMPS...MAY
SEE CONVECTIVE DEVELOPMENT ALONG THE FRONT BY EVENING. POTENTIAL IS
STILL UNCERTAIN AND LIKELY DEPENDS ON CONVECTIVE EVOLUTION ON
SATURDAY NIGHT THAT COULD INFLUENCE THE BOUNDARY LOCATION ON SUNDAY
VIA COOL OUTFLOW AS WELL AS THE BOUNDARY LAYER STABILITY.
NONETHELESS...HAVE KEPT SLIGHT CHANCE TO LOW CHANCE POPS ON SATURDAY
EVENING AND SATURDAY NIGHT.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WERE IN THE REGION THIS
MORNING...AND SHOWERS STILL APPEAR LIKELY AT OMA/LNK THROUGH THE
EARLY MORNING...BUT MOST OF THE THUNDERSTORMS SHOULD REMAIN SOUTH OF
THE TERMINALS. MVFR CIGS AND VISBY ARE POSSIBLE IN THE SHOWERS...BUT
ONCE THIS ACTIVITY MOVES OUT BY EARLY MORNING...VFR CONDITIONS ARE
EXPECTED THROUGH THE REST OF THE PERIOD. SOUTHERLY WINDS WILL
INCREASE THIS AFTERNOON WITH GUSTS FROM MID MORNING THROUGH THIS
EVENING. MAY SEE SOME LLWS OVERNIGHT TONIGHT...BUT THIS APPEARS JUST
OUTSIDE THE TAF WINDOW.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
MAYES/BOUSTEAD