TS Odile

Just figured I'd get a main thread going for the potential impacts of the remnants of Tropical Storm Odile on the Southern Plains to organize the discussion. So far, the Euro has backed off of its prolific rainfall totals (up to 17" SW of OKC) that it showed yesterday, but forecasts keep bouncing around a bit as is to be expected, with the GFS now shifting the swath of heaviest rain into northern OK from southern KS and the 84-hr NAM doing the same.

WPC Discussion

DAY 1

SOUTHWEST INTO THE SOUTHERN PLAINS

WIDESPREAD HEAVY TO EXCESSIVE RAINFALL LIKELY DAY 1 ASSOCIATED

WITH THE CIRCULATION OF ODILE AND WELL TO THE EAST OF THIS

CIRCULATION IN THE MUCH ABOVE AVERAGE PW AXIS THAT WILL STRETCH

FROM SOUTHERN CA/SOUTHERN NV---EASTWARD INTO AZ---NM AND INTO THE

SOUTHERN PLAINS. OBSERVED PW VALUES ACROSS THESE AREAS ARE NEAR

OR ABOVE THE 99 PERCENTILE FOR SEPTEMBER---WITH NO SIGNIFICANT

CHANGES EXPECTED DURING THIS PERIOD TO THESE VALUES. THERE IS A

STRONG MODEL SIGNAL FOR HEAVY TO EXCESSIVE RAINFALL AMOUNTS ACROSS

SOUTHEASTERN AZ---SOUTHERN NM---LEADING TO HIGH CONFIDENCE ACROSS

THESE AREAS. FARTHER TO THE EAST FROM THESE AREAS--THERE IS MORE

MODEL SPREAD WITH HOW QUICKLY HEAVY PRECIPITATION BREAKS OUT INTO

THE SOUTHERN PLAINS. THE HI RES MODELS ARE MORE EMPHATIC ACROSS

THIS AREA---BUT STILL HAVE SOME SIGNIFICANT NORTH-SOUTH

DIFFERENCES WITH THEIR RESPECTIVE AXES. CONFIDENCE IS LOWER

HERE--BUT WITH THE ABOVE MENTIONED HIGH PW AXIS AND MODEL

FORECASTS OF UPPER DIFFLUENCE MAXIMUM IN THIS HIGH PW AXIS---FAVOR

THE HI RES IDEA OF SPREADING HEAVY TO LOCALLY EXCESSIVE RAINFALL

AMOUNTS EASTWARD QUICKER. WHILE MODELS DO NOT DEPICT MUCH

PRECIPITATION ON THE NORTHWESTERN PORTION OF THE ANOMALOUS PW AXIS

FROM SOUTHERN CA INTO SOUTHERN NV AND NW AZ---SCATTERED CONVECTION

LIKELY AGAIN ACROSS THESE AREAS--WITH LOCALLY HEAVY TO EXCESSIVE

RAINFALL AMOUNTS POSSIBLE.

Threw this together from the GFS forecast PWAT and the climatological PWAT graph from OUN to demonstrate their point:

Forecast Offices Graphics

Norman

Amarillo

Drought Monitor

And just for fun, a discussion from the Oklahoma State Climatologist of the heaviest rainfall events in Oklahoma history (all due to tropical remnants):

http://ticker.mesonet.org/select.php?mo=09&da=16&yr=2014