SATELLITE RAINFALL ESTIMATES IN SAB

MOVING FROM IFFA ESTIMATES TO THE

AUTOMATIC ESTIMATOR

Richard Borneman- SATELLITE ANALYSIS BRANCHNESDIS/SATELLITE SERVICES DIVISIONrichard.borneman@noaa.govhttp://www.ssd.noaa.gov

PART 1

BACKGROUND ON SAB PRECIPITATION OPERATIONS

• 1979 First Estimates

• 1983 - Fully Operational– using McIDAS system

– SPENES messages on AFOS

• 1990 - IFFA to Mainframe– much more data

• 1993 - Collocated with HPC into NPPU– better QPF support

• 1995 - Move to OS/2– faster operations

• 1996 - Estimate Graphics to WWW– SSD homepage

• 1997 - Orographic Correction added– for short-term estimates

• 1999 - Moved to Solaris Operating System– Y2K compliant

• 2000 - Combined IFFA/Auto-Estimator Operation

HISTORY OF IFFA/QPE OPERATION

HISTORY OF IFFA/QPE OPERATION

SPRING 2000

SAB begins using the automatic rainfall estimator (AE) for

precipitation operations

Satellite Analysis BranchPrecipitation Products/Services

Satellite Analysis BranchPrecipitation Products/Services

1. SPENES Flash Flood Guidance

2. Satellite Rainfall Estimates

3. Support HPC/NCEP

SPENES ContentsSPENES Contents

1. IFFA Estimates or Auto-Estimates (hourly rates 3-6 hour totals

24 hour totals)2. Satellite Analysis (satellite interpretation - SIM)

3. Nowcast and Satellite Trends

4. Additional Satellite Data In addition to GOES IR & Vis: -Microwave: SSM/I &AMSU (Rain Rate/PW) -GOES Sounder and Imager (PW & LI) -GOES Water Vapor Imagery

* Issued as needed - Using FF guidance and

meteorological judgement

ZCZC NFDSPENES ALL DDHHMM;400,0920 400,0890 380,0890 380,0920;TTAA00 KNFD DDHHMM . SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 7/19/00 0300Z SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678VALUES ARE MAX OR SGFNT EST. NO OROGRAPHIC CORRECTION UNLESS NOTED.......EST'S FM:/GOES8-CNTRL AND E. U.S./GOES10-W. U.S... LATEST DATA USED: GOES-8 0245Z RB AUTO-ESTIMATOR 0230Z. LOCATION...WEST CENTRAL ILLINOIS .EVENT...COULD BE SOME FLASH FLOOD POTENTIAL WITH HEAVY SHOWERS EAST OF STLOUIS..INCRG MCS IS MOVG STDLY SEWD WHICH LIMITS AMTS BUT STILL VRY HVY RNSGIVING AMTS ESTD 2-3"/PST 2-3HRS. THERE WAS A MERGER OF SHWRS INTO TOWRN END OF THIS COMPLEX PST 1-2HRS WHICH ALSO ENHANCED THE RNS.VRY HI MSTR IS AVLBL FOR HVY RNS WITH PW/S ON 00Z RAOBS AND CURRENT GOESSOUNDER NR 2". STG MSTR CONVERGENCE MAX ALG E-W SFC FNT IS CNTRD E OFSTL HELPING TO FOCUS HVY RNS. WV IMAGERY SHOWS CONVECTIVELY INDUCED VORTFM LST NIGHTS KS CONVECTGION MOVG INTO W IL. EVERYTHING MOVG RIGHT ALGSO XPECT BRF FF POTNL FM VRY HVY RATES SEWD INTO S IL/SW IND NEXT FEWHRS..AUTO ESTIMATES.... W IL COUNTIES... HRLY RATE TOTALS TIME MADISON MOVG OUT 2.0"-3.1" 2330-0230Z BOND 1.5-2.5"/HR UP TO 3.4" "....SEE GRAPHIC OF ESTIMATES FOR THIS EVENT ON INTERNET AT THE ADDRESSLISTED BELOW.......SEE HPC QPF GRAPHICS AND DISCUSSIONS FOR FCST....http://www.ssd.noaa.gov/SSD/ML/pcpn-ndx.html [ONLINE SSD PRECIP PRODUCT INDEX] .NNNN

EXAMPLE OF SPENES WITH AUTO-ESTIMATES

PART 2

BACKGROUND ON AUTO-ESTIMATOR AND

EXAMPLES

9

Cloud Top Temperature/Rain Rate Curve for Auto-Estimator

ADDITONAL AE CORRECTIONS/ADJUSTMENTS• 15 min imagery

• Parallax (satellite viewing angle)

• Cloud growth/cloud top cooling and warming

• Moisture correction

• Orographic correction

• Warm cloud tops/ equilibrium level

• Radar reflectivity/ rain- no rain

AUTO-ESTIMATOR PRODUCTS

• Every Half Hour:– Instantaneous Rate– 1 hour totals– 3 hour totals

• Hourly:– 6 hour totals

• Daily (12Z):– 24 hour totals

WEB SITES FOR SATELLITE ESTIMATES

• SSD HOME PAGE– SAB OPERATIONAL PRODUCTS

• http://www.ssd.noaa.gov/SSD/ML/pcpn-ndx.html– SPENES guidance message

– Very high resolution estimate graphics- accompany SPENES’s

• ORA FLASH FLOOD HOME PAGE– AUTO-ESTIMATOR PRODUCTS

• http://orbit-net.nesdis.noaa.gov/arad/ht/ff/index.html– National products in real-time

– Higher resolution by U.S. quadrants

HOW TO USE AE FOR HEAVY RAIN AND FLASH

FLOOD POTENTIAL• Short term maximums (1 to 6 hours)• For moderate/heavy convection (not for light

rains)• Use instantaneous product for very short term

heavy rains (1 hour or less)• Location may be off by 1 or 2 counties with strong

vertical wind shear (check against radar)• Looping of 1 and 3 hour totals good for trends and

movement

EXAMPLE

Auto-Estimates for July 8 – 9, 2000

Northwest Wisconsin/Eastern Minnesota

6 hour Auto-Estimates

ZCZC NFDSPENES ALL DDHHMM;470,0960 470,0890 440,0890 440,0960;

TTAA00 KNFD DDHHMM

.

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 7/9/00 0447Z

THE SATELLITE ANALYSIS BRANCH/NESDIS‑‑‑NPPU‑‑‑TEL.301‑763‑8678

VALUES ARE MAX OR SGFNT EST. NO OROGRAPHIC CORRECTION UNLESS NOTED...

....EST'S FM:/GOES8‑CNTRL AND E. U.S./GOES10‑W. U.S...

LATEST DATA USED: GOES‑8 0432Z CK

AUTOESTIMATOR 0400Z

.

LOCATION...MINNESOTA WISCONSIN

.

EVENT...LATEST CNVCTV TRENDS THRU 0432Z

.

REMARKS...BACK EDGE OF CNVTN HAS BEEN SLIPPING S OVER OTTER TAIL COUNTY/MN..

BUT REMAINS INTENSE WITH SOME BUILDING TWD THE SW. FURTHER EAST..CELL MERGERS

CONTINUE OVER TODD AND MORRISON COUNTIES. NO LET‑UP YET FOR PINE COUNTY.

INTENSE CELLS OVER S AITKIN/MILLE LAC/KANNEBEC COUNTIES ARE DIRFTING S. OVR

WI INTENSE CELL S OF EAU MOVG S.

.

AUTOESTIMATES... 6 HR TOTALS

MN COUNTIES... 22‑04Z

OTTER TAIL/TODD 2" (TOO LIGHT)

CROW WING/AITKIN 2.5"

MN/WI CONTIES...

PINE TO SAWYER 4‑5" MAX AMOUNTS

WI COUNTIES...

CHIPPEWA (N OF EAU) 2.5"

PRICE (W OF RHI) 2.7"

.

SEE GRAPHIC AT ADDRESS BELOW..NOTE..SOME OF THE AMOUNTS MAY BE ON THE LIGHT

SIDE.

...

...SEE HPC QPF GRAPHICS AND DISCUSSIONS FOR FCST...

.

http://www.ssd.noaa.gov/SSD/ML/pcpn‑ndx.html

[ONLINE SSD PRECIPITATION PRODUCT INDEX]

.

SPENES Message that

Was sent

24 hour Reports

CASE STUDY

EASTERN IOWA/NORTHWEST ILLINOIS

May 31, 2000

AUTO ESTIMATES

Vs.

IFFA ESTIMATES

ZCZC NFDSPENES ALL DDHHMM;415,0910 415,0900 420,0890 420,0910;TTAA00 KNFD DDHHMM . SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 5/31/00 1114ZTHE SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678VALUES ARE MAX OR SGFNT EST. NO OROGRAPHIC CORRECTION UNLESS NOTED.......EST'S FM:/GOES8-CNTRL AND E. U.S./GOES10-W. U.S... LATEST DATA USED: GOES-8 1045Z KUSSELSON.LOCATION...EXT E IA/W CENTRAL IL....EVENT...REMAINS OF COLD TOP MCS PRODUCING HVY RAINS.REMARKS...MCS CONTINUES TO SHRINK EXT E IA/WESTERN AND CENTRAL IL...BUT STILL TRAINING ACTIVITY MUSCATINE/CEDAR IA INTO ROCK ISLAND COUNTY(IL)...GENERALLY CLOSE TO WHERE ESTIMATES HAVE REACHED NR 6.0" SINCE 0545Z. MOST OF THE FF THREAT WILL CONTINUE TO SHRINK IN IL AS ADDITIONAL CONVECTION INCRG SE SD/NE NEB MOVES EASTWARD NEXT FEW HRS AND MOVESACROSS SW MN AND W/NW IA. WILL HAVE TO WATCH THIS AREA THIS MORNING FORADDITIONAL HVY RAIN POTENTIAL C IA...WHERE HVY AMOUNTS OCCURRED DURINGTHE NIGHT. .IFFA ESTIMATES...

W CENTRAL IL... TOTALS TIME S ROCK ISLAND 5.8" 0545-1045z N MERCER 5.0" " W HENRY 5.0" " NW KNOX 3.8" "SE IA... LOUISA/MUSCATINE 4.8" "

.

....SEE GRAPHIC OF SATELLITE ESTIMATES FOR PERIOD 0545-1045Z ON THEINTERNET AT ADDRESS BELOW.......SEE HPC QPF GRAPHICS AND DISCUSSIONS FOR FCST.... http://www.ssd.noaa.gov/SSD/ML/pcpn-ndx.html[ONLINE SSD PRECIPITATION PRODUCT INDEX].NNNN SPENES WHICH WAS SENT----BEFORE AE WAS OPERATIONAL

IFFA 24hr. Totals

AE 24hr. Totals

24 HOUR REPORTS

PART 3

USING AUTOMATIC SATELLITE RAINFALL ESTIMATES FOR HEAVY CONVECTIVE RAINFALL

BENEFITS OF USING AE FOR BOTH RAINFALL ESTIMATES AND SAB SPENES GUIDANCE

• More timely

• Greater coverage for whole U.S.

• Continuous coverage

• More frequent SPENES flash flood guidance

EXAMPLE OF IMPROVED SAB PRECIPITATION OPERATIONS

USING AUTO-ESTIMATOR (for first week-started June 12, 2000)

• MORE SPENES MESSAGES- 110 messages; second highest total in 10 years

• BETTER COVERAGE- 54 heavy rain systems for which messages were sent; highest weekly total

• INCREASED TIMELINESS- 21 minutes average time between satellite data and SPENES transmission (compared to 30 min for IFFA)

DEFICIENCIES OF AE ESTIMATES

• Heavy estimates cover too large of an area• Mislocation for shearing cold tops• Overestimates for longer term totals (mostly 24 hour)• Initial estimates low (first hour)• Overestimates for very cold cloud tops with much

cirrus debris• Not good for light amounts• Misses very small short-lived events• Despite auto-adjustment, warm tops often

underestimated.

PART 4

THE FUTURE

FUTURE AUTO-ESTIMATOR IMPROVEMENTS

• Available on AWIPS• Visible Imagery-mostly location of heaviest rains• AMSU/SSMI Microwave-calibrate rain rates• Rain Burst- increase amounts in first hour• Screen Out Lighter Amounts- decrease long-term

overestimates• GOES Multi-Spectral- rain/no-rain; better

amounts