Sept 2nd 12z NCEP model discussion - Communications Prob.

[Stormsfury]

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MODEL DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
119 PM EDT TUE SEP 02 2003

VALID SEP 02/1200 UTC THRU SEP 05/0000 UTC

COMMS PROBLEM AT NCEP LEADING TO SPARSE SFC AND UPR AIR DATA
IN NMAP. THIS MAKES MDL INITIALIZATION A CHALLENGE TDA.

MODEL INITIALIZATION...

AT THE SFC...FROM WHAT LTL DATA IS AVAIL TO VIEW...THE NGM/ETA ARE
TOO WEAK W/THE CYC IN S CNTRL CAN...THE GFS LOOKS BETTER
INITIALIZED HERE. AT H8...THE ETA/GFS/NGM TEMP FIELDS ARE ABOUT 6C
TOO COLD ACRS PORTIONS OF THE DAKOTAS AND NWRN MN. AT H5...THE
TROF SHOULD BE DEPICTED SHARPER ACRS THE MID MS VLY/AR THAN
THE NGM/ETA/GFS INITIALIZE. AT H2...THE ETA/GFS APPEAR 150 NM TOO
FAR NW W/AN UPR CYC NR 33.6N 128.7W ALTHOUGH THEY PICK UP THE
SECOND VORT TO ITS SE PRETTY WELL. HOWEVER...ALL MDLS APPEAR
TO MISS THE FEATURE ON WV NR 23.3N 127.5W.

STRANGELY...WE HAVE ALL THE PW VALUES AVAIL OVR THE CONUS...
EVEN THOUGH WE ARE MISSING OTHER UPR LVL OBS. THE GFS IS THE
BEST INITIALIZED OVERALL. ALL THE MDLS APPEAR TO BE A LTL DRY ALG
THE GA AND SC COAST AS WELL AS NEAR DC.

MODEL TRENDS...

ETA/NGM...
COMPARED THE 00Z RUN LAST NIGHT AND THE 12Z YDA...THE ETA CONTS
TO SPEED UP THE PROGRESS OF THE H5 TROF THRU THE GRTLKS INTO
NEW ENG....WHICH SPEED UP ITS CDFNT MOVMT THRU THE NE QUARTER
OF THE COUNTRY. IT IS DEEPER W/THE SYS CLOSING IN ON THE WEST
COAST TWDS 60 HRS. IN REGARDS TO FABIAN...THE ETA IS TRENDING
SLOWER AND TO THE LEFT THAN ITS PREV RUNS.

GFS...
IT IS ALSO A TOUCH FASTER W/THE TROF MOVG THRU THE GRTLKS AND
NEW ENG.

MODEL DIFFERENCES AND PREFERENCES...

IN THE NORTHEAST...THE GFS REMAINS SLOWER THAN THE ETA W/THE
TROF SWINGING THRU THE GRTLKS. ALSO...THE GFS IS THE DEEPEST OF
ALL THE MDLS. THE GOOD NEWS IS THAT THE GFS/CAN/UKMET AGREE ON
WHERE THE TROF AXIS IS FCST TO MOVE. SINCE THE MDLS ARE
TRENDING WEAKER...WOULD PREFER A SOLN BETWEEN THE UKMET AND
THE WEAKER ETA/CAN...W/A TROF AXIS CLOSER TO THE CONSENSUS
THAN THE ETA.

BECAUSE OF THIS...CAN NOT BUY THE COLD H8 TEMPS THE GFS FCSTS
FOR MN/WRN GRTLKS THRU THE PD. HOWEVER...DO LIKE THE GFS
SLIGHTLY WARMER PATTERN ACRS THE NRN PLAINS/HIGH PLAINS THRU
HR 24 CONSIDERING THE MDLS COLD INITIALIZATION.

ACRS THE ERN GULF OF MEX/SOUTHEAST...THE MDLS DISAGREE ON THE
SPEED ON A SFC CYC THAT IS FCST TO DVLP AND MOV N THEN NEWD
INTO FL. IT APPEARS THAT THERE IS A LOW LVL CIRC FORMING W OF EYW
ATTM...WOULD PREFER THE GFS WHICH SPINS UP AN H8 CIRC OFFSHORE
TAMPA BY MORNING BEFORE RUNNING IT NNE ACRS CEDAR KEY BY THU
AM. AFTER COORD W/THE INTERNATIONAL DESKS...IT APPEARS THAT THE
ETA HAS THE CONVECTION OFFSHORE THE YUCATAN INTIALIZED WELL
WHILE THE GFS HAS THE NRN SYS BETTER INITIALIZED. HENCE...
CONFIDENCE IS LOW. THE ONLY THING CERTAIN IS HVY PCPN IS
EXPECTED SOMEWHERE ACRS NE FL AND THE NRN PENINSULA ON DAY
2 W/TWO POTENTIAL DIST MOVG NNEWD OUT OF THE WRN CARIBBEAN
AND ERN GULF OF MEX. SEE THE QPFPFD FOR MORE INFO ON THE QPF
LATER THIS PM.

ALL THE MDLS BRING AN UPR TROF SLOWLY TWDS THE WEST COAST ON
DAY 2. THE ETA IS THE STRONGEST W/THE FEATURE...WHILE THE
CAN/UKMET/GFS ARE WEAKER W/THE SYS. THE CAN/GFS APPEAR TO
FORM A CONVECTIVE VORT AT HR 36 OVR THE SIERNEV...DRAGGING IT
ENEWD INTO NRN NV. CONSIDERING THAT THERE IS A HIGH FALSE ALARM
RATE OUT WEST W/CONVECTIVE MAXIMA IN THE GFS...CAN NOT TAKE THE
CAN SERIOUSLY. CONSENSUS W//THE WEAKER...NON-CONVECTIVE VORT
SOLN.

AS FOR FABIAN...THE ETA/GFS/UKMET ARE IN STUNNINGLY GOOD
AGREEMENT ON SLOWING DOWN THE SYS A LTL...SHIFTING ITS TRACK A
LTL MORE TO THE SW BY HR 60. THIS IS MOST LIKELY DUE TO A WEAKER
ERN TROF THAN SEEN IN PREV RUNS...WHICH FITS THE LONG TERM MDL
TREND. THE CAN IS THE OUTLIER...TAKING THE CYC MUCH MORE TWDS
THE N...ABOUT 200 NM N OF THE OTHER MDLS. FOR NOW... PREFER THE
CONSENSUS W/FABIAN. SEE THE LATEST ADVISORIES FROM NHC/TPC
CONCERNING THIS CYC.

ROTH