000 ABPZ30 KNHC 011258 TWSEP MONTHLY TROPICAL WEATHER SUMMARY NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 800 AM PDT SAT SEP 1 2007 FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE.. TROPICAL CYCLONE ACTIVITY IN THE EASTERN PACIFIC OCEAN WAS BELOW AVERAGE FOR AUGUST. HURRICANE FLOSSIE AND TROPICAL STORMS GIL AND HENRIETTE FORMED DURING THE MONTH. TROPICAL STORM ERICK ALSO DISSIPATED EARLY IN THE MONTH AFTER THE SYSTEM GENERATED IN JULY. IN COMPARISON...THE AVERAGE AUGUST HAS ABOUT 4 TROPICAL STORMS...2 OF WHICH BECOME HURRICANES. ALTHOUGH THE NUMBER OF TROPICAL STORMS AND HURRICANES IS ONLY SLIGHTLY BELOW AVERAGE...IN TERMS OF THE ACCUMULATED CYCLONE ENERGY (ACE) INDEX...WHICH MEASURES THE COMBINED STRENGTH AND DURATION OF NAMED STORMS AND HURRICANES... THIS WAS THE THIRD QUIETEST AUGUST (BEHIND 1977 AND 1973) SINCE RELIABLE RECORDS BEGAN IN THE EASTERN PACIFIC BASIN IN 1971. ERICK FORMED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN PACIFIC ON 24 JULY. THE WAVE GRADUALLY BECAME BETTER ORGANIZED...FORMING A BROAD SURFACE LOW ALONG THE WAVE ON 28 JULY. THUNDERSTORM ACTIVITY CONSOLIDATED NEAR THE LOW ON 31 JULY AND ORGANIZED INTO A TROPICAL DEPRESSION LATE IN THE DAY...LOCATED ABOUT 925 NM SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. THE DEPRESSION BECAME A TROPICAL STORM EARLY ON 1 AUGUST...REACHING A PEAK INTENSITY OF 35 KT. ERICK WEAKENED INTO A TROPICAL DEPRESSION AT 0000 UTC 2 AUGUST AND DEGENERATED INTO A TROPICAL WAVE SIX HOURS LATER ABOUT 1200 N MI WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. FLOSSIE DEVELOPED FROM AN AREA OF DISTURBED WEATHER THAT HAD BEEN TRACKED WESTWARD ACROSS THE EASTERN NORTH PACIFIC FOR SEVERAL DAYS. THE SYSTEM ORGANIZED INTO A TROPICAL DEPRESSION ON 8 AUGUST CENTERED ABOUT 1100 N MI WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. IT BECAME A TROPICAL STORM BY EARLY ON 9 AUGUST. MOVING GENERALLY WESTWARD...FLOSSIE CONTINUED TO STRENGTHEN AND ON 10 AUGUST AN EYE BECAME EVIDENT...SIGNIFYING THAT THE SYSTEM HAD INTENSIFIED INTO A HURRICANE WHILE CENTERED ABOUT 1200 N MI EAST- SOUTHEAST OF THE HAWAIIAN ISLANDS. FLOSSIE STRENGTHENED FURTHER AND IT BECAME A MAJOR HURRICANE EARLY ON 11 AUGUST...AND A CATEGORY 4 HURRICANE A LITTLE LATER THAT DAY JUST BEFORE CROSSING INTO THE CENTRAL PACIFIC HURRICANE BASIN. FOR FURTHER INFORMATION ON FLOSSIE...SEE THE AUGUST TROPICAL WEATHER SUMMARY BY THE CENTRAL PACIFIC HURRICANE CENTER UNDER WMO HEADER ACPN60 PHFO AND UNDER AWIPS HEADER HFOTWSCP. GIL ORIGINATED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN PACIFIC ON 23 AUGUST. AN AREA OF LOW PRESSURE DEVELOPED ALONG THE WAVE AXIS SOUTH OF THE GULF OF TEHUANTEPEC ON 25 AUGUST. THE LOW MOVED SLOWLY WEST-NORTHWESTWARD OVER THE NEXT SEVERAL DAYS WITH SHOWER AND THUNDERSTORM ACTIVITY GRADUALLY INCREASING. BY THE MORNING OF 29 AUGUST THE SYSTEM GAINED ENOUGH ORGANIZATION TO BE DESIGNATED AS A TROPICAL DEPRESSION...LOCATED ABOUT 220 N MI SOUTH OF THE SOUTHERN TIP OF BAJA CALIFORNIA. DESPITE MODERATE EASTERLY SHEAR...THE DEPRESSION BECAME A TROPICAL STORM JUST SIX HOURS LATER AS CONVECTION INCREASED AND DEEPENED. STRONG HIGH PRESSURE ANCHORED OVER THE SOUTHWESTERN UNITED STATES STEERED GIL ON A GENERAL WESTWARD TRACK FOR THE NEXT SEVERAL DAYS. A STABLE ENVIRONMENT AND EASTERLY SHEAR HAMPERED MUCH STRENGTHENING...AND GIL REACHED A PEAK INTENSITY OF 40 KT AT 1800 UTC 30 AUGUST...ABOUT 330 MILES SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. BY THE END OF THE MONTH GIL WEAKENED TO A TROPICAL DEPRESSION WITH 30 KT WINDS...ABOUT 575 N MI WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. HENRIETTE ORIGINATED FROM A TROPICAL WAVE THAT MOVED OFF THE COAST OF CENTRAL AMERICA ON 28 AUGUST...AND PRODUCED DISORGANIZED SHOWERS AND THUNDERSTORMS FOR THE NEXT DAY OR SO. BY LATE IN THE DAY ON 29 AUGUST A SMALL AREA OF LOW PRESSURE DEVELOPED...ABOUT 305 N MI SOUTH-SOUTHEAST OF ACAPULCO MEXICO. SHOWER AND THUNDERSTORM ACTIVITY SURROUNDING THE LOW IMPROVED IN ORGANIZATION...AND AT 1800 UTC ON 30 AUGUST THE SYSTEM WAS DESIGNATED AS A TROPICAL DEPRESSION...ABOUT 220 N MI SOUTHEAST OF ACAPULCO MEXICO. THE CYCLONE TRACKED TOWARD THE WEST-NORTHWEST IN RESPONSE TO A WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE WESTERN GULF OF MEXICO. THE DEPRESSION GAINED ORGANIZATION AS IT MOVED PARALLEL TO THE SOUTH COAST OF MEXICO AND BECAME TROPICAL STORM HENRIETTE AT 1200 UTC 31 AUGUST...LOCATED ABOUT 75 N MI SOUTH OF ACAPULCO MEXICO. AT MONTH'S END...HENRIETTE WAS ON A STRENGTHENING TREND AND BRINGING RAINFALL AND TROPICAL STORM FORCE WINDS ALONG PORTIONS OF THE PACIFIC COAST OF MEXICO. SUMMARY TABLE NAME DATES MAX WIND (KT) DEATHS ------------------------------------------------------- TS ERICK 31 JUL- 2 AUG 35 0 H FLOSSIE 8 AUG-16 AUG 120 0 TS GIL 29 AUG- 40 0 TS HENRIETTE 30 AUG- 45 * ------------------------------------------------------- NOTE...DATES BASED ON COORDINATED UNIVERSAL TIME (UTC) * UNKNOWN AT THIS TIME $$ FORECASTER BLAKE/MAINELLI