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Tropical Weather Summary


000
ABPZ30 KNHC 011400
TWSEP
MONTHLY TROPICAL WEATHER SUMMARY
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 AM PDT WED AUG 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 JULY. HURRICANE COSME...TROPICAL STORM DALILA...AND
TROPICAL STORM ERICK FORMED IN THE EASTERN PACIFIC DURING THE
MONTH. IN COMPARISON...THE AVERAGE JULY HAS ABOUT FOUR TROPICAL
STORMS...TWO OF WHICH BECOME HURRICANES. TROPICAL DEPRESSIONS
FOUR-E AND FIVE-E ALSO DEVELOPED DURING THE MONTH.

SO FAR IN 2007...THERE HAVE BEEN A TOTAL OF 5 TROPICAL STORMS...1
HURRICANE...AND NO MAJOR HURRICANES.  THESE TOTALS ARE WELL BELOW
THE CLIMATOLOGICAL AVERAGE OF 6.2 TROPICAL STORMS... 3.0 HURRICANES
AND 1.5 MAJOR HURRICANES BY THE END OF JULY. IN FACT...IN TERMS OF
ACCUMULATED CYCLONE ENERGY (ACE)...THIS IS THE THIRD QUIETEST
YEAR-TO-DATE (BEHIND 2005 AND 1966) SINCE THE GEOSTATIONARY
SATELLITE ERA BEGAN IN 1966.

TROPICAL DEPRESSION FOUR-E WAS SPAWNED BY A TROPICAL WAVE THAT
EMERGED FROM THE COAST OF AFRICA ON 23 JUNE AND REACHED THE PACIFIC
ON 3 JULY.  THE ASSOCIATED CONVECTION INCREASED ON 6 JULY AND BEGAN
TO SHOW SIGNS OF ORGANIZATION THE NEXT DAY.  A DEPRESSION FORMED
LATE ON 9 JULY ABOUT 615 N MI SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.  A COMBINATION OF SOUTHWESTERLY VERTICAL WIND SHEAR AND
DECREASING SEA SURFACE TEMPERATURES ALONG THE TRACK PREVENTED
ADDITIONAL STRENGTHENING AS THE CYCLONE MOVED NORTHWESTWARD.  THE
SYSTEM TURNED WESTWARD LATE ON 10 JULY...AND IT WEAKENED TO A
NON-CONVECTIVE REMNANT LOW EARLY THE NEXT DAY ABOUT 765 N MI
WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA.

TROPICAL DEPRESSION FIVE-E DEVELOPED FROM A TROPICAL WAVE THAT MOVED
OFF THE WEST COAST OF AFRICA ON 21 JUNE AND ENTERED THE EASTERN
NORTH PACIFIC AROUND 10 JULY.  DISORGANIZED CONVECTION ASSOCIATED
WITH THE WAVE INCREASED ON 11 JULY.  THE WAVE MOVED WESTWARD AND
GRADUALLY BECAME BETTER ORGANIZED OVER THE NEXT COUPLE OF DAYS, AND
A DEPRESSION FORMED AT 1200 UTC 14 JULY, ABOUT 600 N MI
SOUTH-SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA.  UNDER THE
INFLUENCE OF VERTICAL SHEAR, THE DEPRESSION WAS UNABLE TO
STRENGTHEN FURTHER.  THE CYCLONE CONTINUED WEST-NORTHWESTWARD ON 15
JULY, AND COOLER WATERS AND A MORE STABLE AIRMASS RESULTED IN IT
DEGENERATING INTO A REMNANT LOW AT 0000 UTC 16 JULY.

COSME ORIGINATED FROM A TROPICAL WAVE THAT WAS DIFFICULT TO TRACK
ACROSS THE ATLANTIC AND CARIBBEAN SEA DUE TO THE LACK OF CONVECTIVE
ACTIVITY.  THE WAVE WAS ESTIMATED TO ENTER THE EASTERN NORTH PACIFIC
BASIN AROUND 8 JULY...AND SHOWED SIGNS OF ORGANIZATION STARTING ON
10 JULY.  A TROPICAL DEPRESSION FORMED FROM THE SYSTEM ON 14 JULY
ABOUT 1725 N MI EAST-SOUTHEAST OF HILO HAWAII.  THE DEPRESSION WAS
COMPRISED OF A VERY LARGE CIRCULATION AND INITIALLY MOVED SLOWLY
TOWARD THE NORTHWEST IN RESPONSE TO A WEAKNESS IN THE RIDGE TO THE
NORTH. THE DEPRESSION WAS UPGRADED TO TROPICAL STORM COSME ON 15
JULY...AND WITH BOTH THE ATMOSPHERIC AND OCEANIC ENVIRONMENT
CONDUCIVE FOR STRENGTHENING COSME REACHED HURRICANE STRENGTH 24
HOURS LATER ABOUT 1400 N MI EAST OF HILO HAWAII.  BY EARLY ON 17
JULY...THE CYCLONE MOVED MORE TOWARD THE WEST IN RESPONSE TO A
STRENGTHENING RIDGE TO THE NORTH. BY THIS TIME COSME WAS IN AN
ENVIRONMENT OF MODERATE EASTERLY SHEAR AND WATERS AROUND 25 DEGREES
CELSIUS...AND THE HURRICANE WEAKENED TO A TROPICAL STORM ON 17
JULY.  THE CYCLONE CONTINUED TO SLOWLY WEAKEN AS IT MOVED WESTWARD
AND WAS DOWNGRADED TO A TROPICAL DEPRESSION LATE IN THE DAY ON 18
JULY...JUST PRIOR TO CROSSING INTO THE CENTRAL PACIFIC BASIN.

DALILA DEVELOPED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN
PACIFIC OCEAN ON 17 JULY.  THE WAVE SPAWNED A BROAD LOW PRESSURE
AREA SOUTH OF THE GULF OF TEHUANTEPEC ON 19 JULY.  THE BROAD LOW
MOVED SLOWLY WESTWARD AND THE ASSOCIATED THUNDERSTORM ACTIVITY
INCREASED ON 21 JULY.  THE SYSTEM ACQUIRED ENOUGH ORGANIZATION
EARLY ON 22 JULY TO BE CLASSIFIED AS A TROPICAL DEPRESSION...WHILE
LOCATED ABOUT 400 N MI SOUTH OF MANZANILLO MEXICO.  NORTHEASTERLY
SHEAR INITIALLY INHIBITED SIGNIFICANT STRENGTHENING. HOWEVER...
EARLY ON 23 JULY...THE DEPRESSION WAS ABLE TO REACH TROPICAL STORM
STRENGTH.  A RIDGE OVER NORTHERN MEXICO STEERED DALILA
NORTHWESTWARD DURING THE NEXT FEW DAYS.  THE CYCLONE REACHED A PEAK
INTENSITY OF 50 KT ON 25 JULY WHILE CENTERED ABOUT 50 N MI
SOUTHEAST OF SOCORRO ISLAND.  AFTER PASSING VERY NEAR SOCORRO
ISLAND...DALILA BEGAN MOVING OVER COOLER WATERS WHICH INITIATED
WEAKENING.  ON 26 JULY...WHILE LOCATED ABOUT 210 N MI SOUTHWEST OF
THE SOUTHERN TIP OF BAJA CALIFORNIA THE TROPICAL CYCLONE TURNED
WEST-NORTHWESTWARD AND WEAKENED TO A TROPICAL DEPRESSION EARLY THE
NEXT DAY.  DALILA DEGENERATED TO A REMNANT LOW ON 27 JULY...ABOUT
400 N MI WEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA.  THE REMNANT
LOW MOVED WEST-NORTHWESTWARD DURING THE NEXT FEW DAYS AND
DISSIPATED ON 30 JULY.

ERICK FORMED FROM A TROPICAL WAVE THAT ENTERED THE EASTERN PACIFIC
ON 23 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 960 NM SOUTHWEST OF THE
SOUTHERN TIP OF BAJA CALIFORNIA.  THE DEPRESSION BECAME A TROPICAL
STORM EARLY ON 1 AUGUST AND AT THE TIME OF THIS WRITING WAS LOCATED
ABOUT 1075 NM WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.


SUMMARY TABLE

NAME             DATES         MAX WIND (KT)     DEATHS
-------------------------------------------------------
TD FOUR-E        9-11 JUL          30                0
TD FIVE-E       14-15 JUL          30                0
H  COSME        14-23 JUL          65                0
TS DALILA       22-27 JUL          50                0
TS ERICK        31 JUL-            35                0
-------------------------------------------------------

NOTE...DATES BASED ON COORDINATED UNIVERSAL TIME (UTC)

$$

FORECASTER BLAKE/MAINELLI/RHOME/BROWN