389  
FNUS72 KFFC 181205  
FWSFFC  
 
SPOT FORECAST FOR HITCHITI GROUND IGNITIONS...UNITED STATES FOREST SERVICE  
NATIONAL WEATHER SERVICE PEACHTREE CITY GA  
805 AM EDT THU APR 18 2019  
 
FORECAST IS BASED ON IGNITION TIME OF 0800 EDT ON APRIL 18.  
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
DISCUSSION
 
 
STRONG, 15 TO 25 MPH, TRANSPORT WINDS FROM THE SOUTH ALONG WITH A  
RELATIVELY DEEP MIXED LAYER, WILL ALLOW FOR POTENTIALLY GOOD SMOKE  
DISPERSAL BY LATE MORNING INTO THE AFTERNOON DESPITE FAIRLY EXTENSIVE  
CLOUD COVER. WE WILL SEE VARYING DEGREES OF OPAQUENESS TO THE HIGHER  
LEVEL CLOUDS THROUGH MUCH OF THE DAY WITH THICKER, LOWER CLOUD COVER  
MOVING INTO THE AREA BY LATE AFTERNOON. ADI STARTS OUT "POOR TO FAIR"  
THIS MORNING, BUT SHOULD REACH INTO THE "GENERALLY GOOD" RANGE BY  
LATE MORNING TO MIDDAY. MAY SEE A FEW HOURS WHERE THE ADI REACHES THE  
"VERY GOOD" RANGE MID TO LATE AFTERNOON. SHOULDN'T SEE RELATIVE  
HUMIDITY VALUES DROP BELOW 60 PERCENT UNTIL AROUND NOON TO 1 PM,  
BOTTOMING OUT AROUND 45 PERCENT LATE IN THE AFTERNOON.  
   
REST OF TODAY
 
 
SKY/WEATHER.........MOSTLY CLOUDY (60-70 PERCENT).  
CWR.................10 PERCENT.  
LAL.................NO TSTMS.  
MAX TEMPERATURE.....AROUND 81.  
MIN HUMIDITY........46 PERCENT.  
WIND (20 FT)........LIGHT WINDS BECOMING SOUTH 5 TO 9 MPH LATE IN THE  
MORNING AND 8 TO 12 MPH IN THE AFTERNOON.  
MIXING HEIGHT.......4800-5200 FT AGL.  
TRANSPORT WINDS.....SOUTH 15 TO 25 MPH.  
SMOKE DISPERSAL.....POOR (3400 KNOT-FT) EARLY IN THE MORNING  
INCREASING TO EXCELLENT (102900 KNOT-FT) IN THE  
AFTERNOON INCREASING TO EXCELLENT (114000  
KNOT-FT) LATE IN THE AFTERNOON.  
LVORI...............3.  
ADI.................20 INCREASING TO 70.  
HAINES INDEX........3 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE  
PLUME DOMINATED FIRE GROWTH.  
PCPN AMOUNT.........0.00 INCHES.  
CEILING (KFT).......25 DECREASING TO 20 LATE IN THE MORNING, THEN  
DECREASING TO 15 LATE IN THE MORNING DECREASING  
TO 12 LATE IN THE MORNING DECREASING TO 5.0  
INCREASING TO 6.0 LATE IN THE AFTERNOON.  
 
TIME (EDT) 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........70 60 65 65 65 65 70 70 65 70  
WEATHER COV.....  
WEATHER TYPE....  
TSTM COV........  
CWR.............10 10 10 10 10 10 10 10 10 10  
LAL.............1 1 1 1 1 1 1 1 1 1  
TEMP............61 64 67 71 74 76 78 80 81 81  
RH..............94 87 80 74 66 60 55 51 48 46  
20 FT WIND DIR..SE S S S S S S S S S  
20 FT WIND SPD..3 4 6 7 8 9 10 11 10 10  
20 FT WIND GUST.6 7 9 12 13 14 16 17 16 14  
MIX HGT (KFT)...0.2 0.9 2.3 2.5 3.0 3.5 4.0 4.5 5.0 5.0  
TRANSP WIND DIR.S S S S S S S S S S  
TRANSP WIND SPD.23 21 18 18 18 18 20 21 23 25  
LVORI...........5 4 3 3 1 1 1 1 1 1  
ADI.............20 24 52 52 58 49 55 62 70 70  
HAINES INDEX....3 3 3 4 4 4 3 3 3 4  
VRATE KT-FT/1K..3 13 31 40 47 62 70 81 103 114  
VENTRATE CAT....PR PR PR PR FR GD GD GD VGD VGD  
CEILING (KFT)...25 20 15 12 5.0 5.0 5.0 5.0 6.0 6.0  
   
TONIGHT
 
 
SKY/WEATHER.........MOSTLY CLOUDY (75-85 PERCENT). SHOWERS LIKELY  
AND CHANCE OF THUNDERSTORMS OVERNIGHT.  
CWR.................10 PERCENT INCREASING TO 70 PERCENT.  
LAL.................NO TSTMS UNTIL 0200, THEN 9-15 STRIKES.  
MIN TEMPERATURE.....AROUND 67.  
MAX HUMIDITY........92 PERCENT.  
WIND (20 FT)........SOUTH WINDS 8 TO 13 MPH. GUSTY AND ERRATIC  
WINDS EXPECTED NEAR THUNDERSTORMS OVERNIGHT.  
MIXING HEIGHT.......300 FT AGL.  
TRANSPORT WINDS.....SOUTH 26 TO 32 MPH INCREASING TO 48 TO 56 MPH.  
SMOKE DISPERSAL.....EXCELLENT (87800 KNOT-FT) EARLY IN THE EVENING  
DECREASING TO POOR (9000 KNOT-FT) LATE IN THE  
NIGHT.  
LVORI...............3.  
ADI.................66 DECREASING TO 30 EARLY IN THE EVENING, THEN  
INCREASING TO 40 IN THE LATE EVENING AND  
OVERNIGHT INCREASING TO 49 AFTER 3 AM.  
HAINES INDEX........3 TO 5 OR VERY LOW TO MODERATE POTENTIAL FOR  
LARGE PLUME DOMINATED FIRE GROWTH.  
PCPN AMOUNT.........0.38 INCHES.  
CEILING (KFT).......6.0 INCREASING TO 8.0 EARLY IN THE EVENING,  
THEN DECREASING TO 7.0 EARLY IN THE EVENING  
INCREASING TO 10 LATE IN THE EVENING DECREASING  
TO 8.0 DECREASING TO 3.0 OVERNIGHT DECREASING  
TO 1.0 INCREASING TO 1.5 EARLY IN THE MORNING.  
 
TIME (EDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM  
SKY (%).........64 67 67 69 76 79 80 81 82 86 95 99  
WEATHER COV..... SCH CHC CHC CHC LKY LKY  
WEATHER TYPE.... RW RW RW RW RW RW  
TSTM COV........ CHC CHC CHC CHC  
CWR.............10 10 10 10 10 10 20 30 40 50 60 70  
LAL.............1 1 1 1 1 1 1 1 3 3 3 3  
TEMP............81 80 78 76 74 72 71 69 68 68 68 68  
RH..............47 49 52 54 58 62 68 74 78 83 86 89  
20 FT WIND DIR..S S S S S S S S S S S S  
20 FT WIND SPD..9 8 8 8 9 9 9 9 10 10 12 13  
20 FT WIND GUST.12 11 10 11 12 13 13 14 14 14 17 17  
MIX HGT (KFT)...3.1 0.4 0.3 0.4 0.4 0.5 0.5 0.5 0.6 0.7 0.8 0.9  
TRANSP WIND DIR.S S S S S S S S S S S S  
TRANSP WIND SPD.26 30 32 37 40 44 45 45 45 48 53 56  
LVORI...........1 2 2 1 1 1 3 3 3 3 4 4  
ADI.............66 26 29 33 36 39 40 40 41 44 47 51  
HAINES INDEX....4 4 4 4 4 5 5 5 3 3 3 3  
VRATE KT-FT/1K..88 35 9 12 17 19 20 22 23 29 40 46  
VENTRATE CAT....GD PR PR PR PR PR PR PR PR PR FR FR  
CEILING (KFT)...6.0 8.0 7.0 7.0 7.0 10 12 8.0 3.0 1.0 1.0 1.5  
   
FRIDAY
 
 
SKY/WEATHER.........MOSTLY CLOUDY (80-90 PERCENT). SHOWERS AND  
CHANCE OF THUNDERSTORMS IN THE MORNING, THEN  
SHOWERS LIKELY EARLY IN THE AFTERNOON. CHANCE  
OF SHOWERS LATE IN THE AFTERNOON.  
CWR.................80 PERCENT INCREASING TO 100 PERCENT EARLY IN  
THE MORNING, THEN DECREASING TO 90 PERCENT  
EARLY IN THE MORNING DECREASING TO 80 PERCENT  
LATE IN THE MORNING DECREASING TO 70 PERCENT  
DECREASING TO 60 PERCENT EARLY IN THE AFTERNOON  
DECREASING TO 50 PERCENT.  
LAL.................9-15 STRIKES UNTIL 1300, THEN NO TSTMS.  
MAX TEMPERATURE.....AROUND 69.  
MIN HUMIDITY........65 PERCENT.  
WIND (20 FT)........WEST WINDS 9 TO 13 MPH WITH GUSTS TO AROUND 18  
MPH. GUSTY AND ERRATIC WINDS EXPECTED NEAR  
THUNDERSTORMS.  
MIXING HEIGHT.......4500 FT AGL.  
TRANSPORT WINDS.....SOUTH 60 TO 62 MPH DECREASING TO AROUND 49 MPH  
LATE IN THE MORNING, THEN BECOMING SOUTHWEST  
AND DECREASING TO AROUND 36 MPH LATE IN THE  
MORNING BECOMING WEST 23 TO 29 MPH LATE IN THE  
MORNING.  
SMOKE DISPERSAL.....GOOD (31100 KNOT-FT) EARLY IN THE MORNING  
INCREASING TO EXCELLENT (110400 KNOT-FT) IN THE  
AFTERNOON.  
LVORI...............3.  
ADI.................54 INCREASING TO 71 EARLY IN THE MORNING, THEN  
DECREASING TO 58 LATE IN THE MORNING DECREASING  
TO 42 LATE IN THE MORNING INCREASING TO 56  
INCREASING TO 69 EARLY IN THE AFTERNOON  
INCREASING TO 80.  
HAINES INDEX........2 TO 4 OR VERY LOW TO LOW POTENTIAL FOR LARGE  
PLUME DOMINATED FIRE GROWTH.  
PCPN AMOUNT.........0.89 INCHES.  
CEILING (KFT).......1.2 DECREASING TO 1.0 LATE IN THE AFTERNOON.  
 
TIME (EDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM  
SKY (%).........99 99 99 98 97 96 96 93 87 82 77 74  
WEATHER COV.....DEF DEF DEF DEF DEF DEF DEF LKY LKY LKY CHC CHC  
WEATHER TYPE....RW RW RW RW RW RW RW RW RW RW RW RW  
TSTM COV........CHC CHC CHC CHC CHC CHC CHC  
CWR.............80 100 90 90 90 80 80 70 60 60 50 50  
LAL.............3 3 3 3 3 3 3 1 1 1 1 1  
TEMP............68 68 67 67 67 67 68 68 67 65 63 61  
RH..............90 91 91 92 92 90 85 78 72 70 68 67  
20 FT WIND DIR..S S S S S S SW SW SW SW W W  
20 FT WIND SPD..13 12 12 12 12 10 10 9 9 9 10 12  
20 FT WIND GUST.18 17 17 16 16 14 14 13 12 13 14 16  
MIX HGT (KFT)...0.9 0.9 0.8 1.0 1.3 1.4 1.9 2.9 3.4 3.7 4.2 4.5  
TRANSP WIND DIR.S S S S SW W W W W W W W  
TRANSP WIND SPD.60 62 60 49 36 25 23 24 25 26 28 29  
LVORI...........4 4 4 4 4 4 4 3 3 1 1 1  
ADI.............54 74 67 62 53 40 43 56 66 71 78 82  
HAINES INDEX....3 3 2 2 2 4 4 4 3 3 3 3  
VRATE KT-FT/1K..45 44 43 40 34 31 43 66 77 86 102 110  
VENTRATE CAT....FR FR FR FR PR PR FR GD GD GD VGD VGD  
CEILING (KFT)...1.5 1.2 1.2 1.2 1.5 1.5 1.5 1.5 1.5 1.5 1.2 1.0  
 

 
FORECASTER...SENA  
REQUESTED BY...CHARLES GRAY  
TYPE OF REQUEST...PRESCRIBED  
.TAG 1906409.1/FFC  
.DELDT 04/18/19  
.FORMATTERVERSION 1.0.26  
.EMAIL CGRAY@FS.FED.US  
 
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