Understanding Written Weather Reports

How many of you can predict the future?

Forecasting Methods

• Persistence Method.• Wake in the morning to sunshine• Usually good for a couple of hours

• Trend Forecast• Front moving toward the airport at 30 MPH• You are 60 miles away from the front• It will be here in 2 hours• Good for a few hours• Nowcasts

Forecasting Methods

• Climatological Forecast• Average for region• Examples?

• Analogue Forecasts• Compares current weather charts with those from the past.• Usually only good for temps

Forecasting Methods• Meteorological Forecasts• One of the more accurate• Uses the forecasters scientific knowledge of atmospheric process

to generate a weather prediction.• 6-12 hour forecasts

• Numerical Weather Prediction• Uses powerful computers and complex software• Represents the physical laws which govern the behavior of the

atmosphere.• 5-10 minutes of forecasting constantly repeating itself

Compiling & Processing• Observation• Communication• Processing• Dissemination

Observation

At sea, on land, & in the sky

Weather Forecast Office (WFO)2 a day, 11z and 23z20 miles in altitude then

balloon will popParachute down to ground Instructions inside to returnThere is minimal risk, but the

small components will probably not hurt the aircraft.

10% come back to the officeCrucial to the full forecast opsAll over the world at the same

time

Communication• Transmitted by telephone, computer, or satellite to a

communication substation for subsequent relay to one of 3 Meteorological Centers• Washington, DC• Moscow, Russia• Melbourne, Australia

Processing• From these centers, info is sent to National Centers for

Environmental Predictions (NCEP).• Focus for US wx predictions• Super computer does the forecasting• 20,000 different types of text reports• 6,000 different graphic reports

Dissemination• Info produced by the NCEP is sent to NWS Facilities across the

country.• Some NWS’s have Wx Forecast Offices (WFO’s)• NEXRAD

A forecast is just that, an educated guess.

Remember, the further ahead in time the forecast is, the less accurate it

becomes.

Printed WX Reports• METAR• TAF• Area Forecast• Winds & Temp Aloft

METAR• Aviation Routine Weather Report• Once an hour• If a significant change to one or more items in the METAR,

then the Non-Routine METAR (SPECI) is released.

METAR KCSG 131351Z 00000KT 9SM CLR 20/16 RMK AO2 SLPNO T02000161 $

• METAR – Type of report• KCSG – Station Identifier• 131351Z – Time of report• 00000KT – Wind Information• 9SM – Visibility• CLR – Weather (Sky Condition)• 20/16 – Temperature/Dew point• RMK – Remarks• AO2 – Precipitation Discriminator• SLPNO – Sea level pressure not operational• T02000161 – True Temp & Dew Point

METAR• Visibility• Prevailing is what a person will see• RVR is a machine (transmissometer)• If less than 6SM, it has to tell you why

• FG,BR,HZ,FU

METAR• Sky conditions are reported in 1/8 coverage• Reported as AGL• CLR – Sky is Clear• FEW – There are few clouds, Zero to 2/8• SCT – Clouds are Scattered, 3/8 – 4/8• BKN – Cloud Layer is Broken, 5/8 -7/8• OVC – The Cloud Layer is Overcast, 8/8

• Can report Cloud type also.• TCU• CB

KORD 131451Z VRB03KT 8SM -RA FEW012 SCT046 OVC055 13/11 A3009 RMK AO2 TSE00RAE1354B10 SLP188 OCNL LTGICCG DSNT E-SE CB DSNT E-SE P0006 60010 T01330106 51017

Terminal Area Forecast (TAF)• Valid for 24 Hours• Comes out every 6 hours (Four times a day)• 0000Z, 0600Z, 1200Z, 1800Z• Can be amended

• All cloud heights are AGL

TAF

KORD 131505Z 1315/1418 36008KT P6SM BKN050 BKN090

FM131700 35009G17KT P6SM SCT040 SCT100 BKN250

FM131900 34013G22KT P6SM FEW050 SCT250 FM140000

33008KT P6SM SCT250

FM141300 28008KT P6SM BKN250

TAF• OVC010CB• BECMG 0610• TEMP0 1923• -TSRA• PROB30 0004

Aviation Area Forecast (FA)• Covers a wide region• Used when your destination does not have a TAF• Good for enroute wx• Good for 12 hours• Comes out 3 times a day• 0000Z, 0800Z, 1600Z

• May have a categorical outlook• 6 Hours

FA• 4 main parts• Communication & Product Header• Precautionary Statement• 2 weather sections

• Synopsis• VFR Clouds & Weather

FA

MIAC FA 131310AMD SYNOPSIS AND VFR CLDS/WXSYNOPSIS VALID UNTIL 140300CLDS/WX VALID UNTIL 132100...OTLK VALID 132100-140300NC SC GA FL AND CSTL WTRS E OF 85W

SEE AIRMET SIERRA FOR IFR CONDS AND MTN OBSCN. TS IMPLY SEV OR GTR TURB SEV ICE LLWS AND IFR CONDS. NON MSL HGTS DENOTED BY AGL OR CIG.

SYNOPSIS...CDFNT XTRM SW OH SEWD ACRS SRN WV-SWRN VA-NERN NC MOVG SWD. BY 18Z WRMFNT WRN OH-SWRN WV-SWRN VA-WRN NC-SERN NC INTO CSTL WTRS. BY 03Z LOW E CNTRL OH. CDFNT SWRN WV-SWRN VA-NWRN NC- SERN NC INTO CSTL WTRS. CDFNT MIDDLE TN-NWRN AL TO SERN LA. BY 15Z CDFNT CNTRL GA-FL PNHDL INTO NERN GULF MEX DSIPTG 18Z-21Z.

. NC ...UPDT CSTL PLAIN...SCT080 BKN150 TOP FL250. 17Z BKN100. ISOL -SHRA/ -TSRA. CB TOP FL380. OTLK...VFR. 00Z MVFR BR. PIEDMONT...BKN100 LYRD FL250. ISOL -SHRA. 14Z BKN080. ISOL -SHRA. OTLK...VFR. APLCNS...BKN120 LYRD FL250. IN VLYS VIS 3SM BR. 13Z BKN070 LYRD FL200. SCT -SHRA. OTLK...VFR. . SC CSTL PLAIN...SCT100 BKN CI. 13Z BKN100 LYRD FL200. ISOL -SHRA. 18Z SCT100 BKN CI. OTLK...VFR. PIEDMONT...SCT120 BKN CI. OCNL BKN120 LYRD FL200. ISOL -SHRA. BECMG 1518 SCT100 BKN CI. OTLK...VFR. APLCNS...SCT060 BKN100 TOP FL200. ISOL -SHRA. OTLK...VFR. . GA APLCNS-N GA...BKN090 LYRD FL250. WDLY SCT -SHRA. 13Z BKN100 TOP 150. OTLK...VFR. CNTRL GA...SCT060 BKN090 LYRD FL220. OCNL BKN060. VIS 5SM WDLY SCT -SHRA BR. BECMG 1517 SCT060 SCT100. OTLK...VFR

. SWRN GA...SCT020 BKN080 TOP 140. OCNL BKN020. ISOL -SHRA. VIS OCNL 3SM BE. 13Z SCT050 SCT100. 17Z ISOL -SHRA. OTLK...VFR. SERN GA-CSTL PLAIN...SCT050 BKN090 TOP 120. OCNL VIS 3SM BR. ISOL -SHRA. 15Z SCT050 SCT100. OTLK...VFR. . FL ...UPDT W PNHDL...SCT025 BKN090 TOP 120. OCNL BKN025 TOP 040. VIS 5SM BR. 13Z SCT040. 16Z ISOL -SHRA. OTLK...VFR. E PNHDL...SCT100. VIS 5SM BR. 13Z SCT050. 16Z ISOL -SHRA. OTLK...VFR. N FL...SCT070 SCT CI. VIS 3SM BR. 13Z SCT040. OTLK...VFR. CNTRL FL...SCT070 BKN CI. OTLK...VFR. S FL...BKN050 BKN120 LYRD FL250. OCNL BKN035. ISOL -SHRA. 20Z SCT050 BKN100. OTLK...VFR. FL KEYS...SCT020 BKN090 LYRD FL250. OCNL BKN050. VIS 5SM SCT -SHRA/-TSRA. CB TOP FL450. OTLK...VFR. . CSTL WTRS ...UPDT ATLC WTRS NC...SCT070 BKN100 LYRD FL250. ISOL -SHRA/-TSRA. CB TOP FL400. BECMG 1821 BKN090. VIS 5SM SCT -SHRA/-TSRA. CB TOP FL370. OTLK...MVFR SHRA.

SC-GA - W HLF...SCT100 BKN CI. BECMG 1821 OCNL BKN100 TOP 140. WDLY SCT -SHRA. OTLK...VFR. E HLF...SCT030 BKN080 TOP 150. WDLY SCT -SHRA/ISOL -TSRA. CB TOP FL400. OTLK...VFR. FL PBI NWD-E 80W SRN THIRD...BKN070 TOP 120. WDLY SCT -SHRA. 15Z SCT -TSRA. CB TOP FL430. OTLK...VFR. RMNDR...SCT090 BKN CI. 15Z OCNL BKN090 TOP 140. WDLY SCT -SHRA. OTLK...VFR. PBI NWD-W 80W...SCT070 BKN CI. 18Z SCT040 SCT100 BKN CI. OTLK...VFR. S PBI THRU FL STRAIT...BKN050 LYRD FL250. VIS 5SM SCT TSRA. CB TOP FL450. OTLK...VFR. GULF WTRS E OF 85W S RSW...BKN070 LYRD FL250. SCT -TSRA. CB TOP FL450. BECMG 1821 SCT080 BKN CI. ISOL -SHRA. OTLK...VFR. RMNDR S HLF...SCT060 BKN CI. OTLK...VFR. N HLF...SCT050. BECMG 1618 ISOL -SHRA. OTLK...VFR. ....

FA• Clouds Height is MSL unless otherwise noted

Winds & Temperatures Aloft Forecasts (FD)• True North• Speed shown in Knots• Temps in Celsius• DOES NOT include levels within 1,500 feet of station elevation• Temperatures not forecasted for the 3,000-foot level OR if

station elevation is within 2500• All temps over FL240 are negative• All wind velocities over 100 have special coding

FD• VALID 131800Z FOR USE 1400-2100Z. TEMPS NEG ABV 24000

• FT 3000 6000 9000 12000 18000 24000 30000 34000 39000• EYW 1907 2307+15 2305+11 2407+06 3011-06 2919-16 262131 243041 234153• JAX 2707 2815+12 2619+06 2628+02 2851-06 2757-19 267732 269241 259652• MIA 0408 1708+14 1912+10 2310+05 2727-06 2621-15 253131 243641 244953• MLB 9900 2415+13 2621+10 2626+04 2732-06 2742-16 265631 255741 256553• PFN 2707 2917+11 2721+06 2825+04 2732-06 2745-20 267134 258841 249352• PIE 9900 2713+14 2619+09 2624+04 2825-05 2739-17 265931 256141 246452• TLH 2707 2718+11 2724+05 2729+03 2840-06 2749-19 267533 269041 259552• ATL 2405 2506+09 2707+03 2511-02 2937-10 2864-20 276237 267944 268952• CSG 9900 2715+09 2809+04 2917+01 2944-08 2763-20 276436 269042 269352• SAV 2408 2808+10 2619+05 2621-01 2852-08 2859-19 276934 269641 760551• HAT 9900 2407+13 2611+04 2821-03 2725-15 2633-27 277637 279442 278751• ILM 2513 2906+12 2610+04 2717-01 2719-15 2729-25 279134 279142 279851• RDU 1009 2209+11 2706+04 2715-03 2608-15 2816-27 274940 278642 278451• CAE 9900 9900+10 2811+04 2615-02 2716-14 2860-20 277735 268843 269852• CHS 2209 2608+10 2720+05 2819-01 2733-13 2871-19 277135 269741 760352• FLO 1805 9900+11 3013+04 2815-01 2814-14 2626-25 279034 278943 279751• GSP 9900 9900+10 2608+03 2409-02 2512-13 2716-24 288335 277744 268951• 2XG 2310 2313+12 2522+08 2734+02 2653-07 2661-18 268131 269041 269753

FD• Winds over 100 knots• 760551• 76 05 51• Wind direction, subtract 50• Wind Velocity add 100• Keep the temp as is• So, Winds are 260 @ 105 knots w/ temp of -50C

Weather Briefing• 1-800-WX-BRIEF or 1-800-992-7433• Not your old wx briefing service• Now run by Lockheed Martin• They know who you are when you call them• Quicker filing with the new services, because they have all of

your info on file

Weather Briefing

1. Adverse Conditions2. VFR Flight not Recommended3. Synopsis4. Current Conditions5. Enroute Forecast6. Destination Forecast7. Winds & Temps Aloft8. Notices to Airmen9. ATC Delays10. Requests for Pireps11. EFAS12. Other Information

Wx Briefing• Standard• Abbreviated• Outlook

Wx Briefing• EFAS• Flight Watch• 122.0

Wx Briefing• TWEB• Transcribed Weather Broadcast• Transmitted over select VOR’s & NDB’s

Wx Briefing• HIWAS• Hazardous In-flight Weather Advisory Service• On selected VOR’s• Center will advise if updated