LOW CLOUDS AND IFR FORECASTING NATIONAL WEATHER SERVICE KEN WIDELSKI October 11, 2005

BACKGROUND  GLEN COVE, NEW YORK  12/99-09/01: NWS UPTON, NY  11/01-02/02: METRO WEATHER SERVICE  03/02-04/04: NWS AUSTIN/SAN ANTONIO  04/04-PRESENT: NWS LUBBOCK

AGENDA  BASIC PROCESSES  FORECAST FACTORS  FLIGHT CATEGORIES – REVIEW  NWS AVIATION SOFTWARE/ PRODUCTS  TOOLS OF THE TRADE  YOU MAKE THE CALL- INTERACTIVE  CONCLUSION

BASIC PROCESSES  A) LOW CLOUDS - INGREDIENTS I: MOISTURE TRANSPORT (WAA) I: MOISTURE TRANSPORT (WAA) 2: LOW LEVEL JET (LLJ) 2: LOW LEVEL JET (LLJ) 3: SURFACE WIND FLOW 3: SURFACE WIND FLOW 4: UPSLOPE FLOW 4: UPSLOPE FLOW

BASIC PROCESSES  B) FOG –TYPES AND INGREDIENTS 1: RADIATION 1: RADIATION -WIND SPEED 5 KTS OR LESS -WIND SPEED 5 KTS OR LESS -CLEAR TO PARTLY CLOUDY -CLEAR TO PARTLY CLOUDY -SOIL MOISTURE -SOIL MOISTURE 2: ADVECTION 2: ADVECTION -MOISTURE TRANSPORT -MOISTURE TRANSPORT 3: UPSLOPE 3: UPSLOPE

NAME THAT FOG! NAME THAT FOG!

HOW ABOUT THIS ONE?

AND FINALLY…

FORECAST FACTORS  CAPROCK

FACTORS CON’T  A DISTANT MOISTURE SOURCE

FACTORS CONT’D  SLOPING TERRAIN TO THE WEST

FAA FLIGHT CATEGORIES  VFR - Visual Flight Rules; Visibility > 5 SM Ceiling > 3000 feet Ceiling > 3000 feet  MVFR - Marginal Visual Flight Rules; Visibility 3 to 5 SM; Ceiling 1000 to 3000 feet  IFR - Instrument Flight Rules; Visibility 1 to <3 statute miles; Ceiling 500 to 900 feet  LIFR - Low Instrument Flight Rules; Visibility <1 statute mile; Ceiling < 500 feet

SOFTWARE AND PRODUCTS  TAF - TERMINAL AERODROME FORECAST - TERMINAL AERODROME FORECAST - 5 NM HOLE AROUND CENTER OF - 5 NM HOLE AROUND CENTER OF RUNWAY COMPLEX RUNWAY COMPLEX - FOUR ROUTINE ISSUANCES PER DAY - FOUR ROUTINE ISSUANCES PER DAY 12Z, 18Z, 00Z AND 06Z 12Z, 18Z, 00Z AND 06Z - SITES: KLBB AND KCDS - SITES: KLBB AND KCDS

LOW CLOUD TAF KLBB Z KT P6SM SCT020 SCT200 TEMPO SM –TSRA BKN035CB TEMPO SM –TSRA BKN035CB FM KT P6SM –SHRA SCT020 OVC050 FM KT P6SM –SHRA SCT020 OVC050 FM KT 4SM BR BKN010 FM KT 4SM BR BKN010 FM KT 2SM BR BKN006 OVC010 FM KT 2SM BR BKN006 OVC010 FM KT P6SM SCT020 SCT120 FM KT P6SM SCT020 SCT120

NWS TAF SOFTWARE  AVNFPS -PART OF AWIPS -PART OF AWIPS

 TWEB - TRANSCRIBED WEATHER BROADCAST - TRANSCRIBED WEATHER BROADCAST - TWEB ROUTE: 50 NM WIDE CORRIDOR - TWEB ROUTE: 50 NM WIDE CORRIDOR ALONG A LINE CONNECTING THE ALONG A LINE CONNECTING THE ANCHOR POINTS OF THE ROUTE. ANCHOR POINTS OF THE ROUTE. - FOUR ISSUANCES PER DAY - FOUR ISSUANCES PER DAY - KAMA-KLBB-KMAF - KAMA-KLBB-KMAF

LOW CLOUD TWEB LOW CLOUD TWEB 185 TWEB KAMA-KLBB-KMAF. ALL HGTS AGL EXC TOPS. KAMA-KPVW P6SM –RA SCT020 OVC040 AREAS 4SM TSRA BKN020CB…07Z P6SM SCT010 OVC030 AREAS 2SM BR SHRA OVC010. KPVW-KMAF P6SM SCT020 BKN050 SCT 5SM –RA BR OVC015.

TWEB EDITOR

TOOLS OF THE TRADE A) UPPER AIR OR MODEL SOUNDINGS A) UPPER AIR OR MODEL SOUNDINGS

B) VAD WIND PROFILER

C) * SATELLITE DATA * C) * SATELLITE DATA *

Equipment Used By The NWS To Monitor The Weather Imagery From Space Satellites

D) LOCAL OBSERVATIONS

E) MODEL STATISTICS  FOUS14 KWBC (Forecast office and name, date/time) DCA ESC NGM MOS GUIDANCE 3/06/ UTC DAY /MAR 6 /MAR 7 /MAR 8 HOUR MX/MN TEMP DEW CLDS OV OV OV OV OV OV OV OV OV OV BK BK BK SC SC SC CL CL CL WDIR WSPD CIG VIS OBVIS H H H N N N N F F F F H N

YOU MAKE THE CALL

HEAD TO WORK

SAY HELLO TO THE MIC

LOW CLOUDS AND FOG ROLL IN

THE NEW DATA SHOWS…  1 MILE VISIBILITY IN FOG  600 FOOT BROKEN CEILING

WHAT FLIGHT CATEGORY?  A) MVFR  B) IFR  C) LIFR  D) VFR  E) LIFR VISIBILITY IFR CEILING IFR CEILING

ANSWER  I I I IFR !!

CONCLUSION  GOOD UNDERSTANDING OF BASIC PROCESSES CAN MAKE FOR BETTER PLANNING AND PREPARATION.  MUCH DATA AVAILABLE VIA WEB  NWS SINCE 1870 – DEDICATED TO PROVIDING QUALITY PRODUCTS TO THE SOUTH PLAINS