476
WTPZ43 KNHC 090857
TCDEP3
TROPICAL STORM RACHEL DISCUSSION NUMBER 49
NWS NATIONAL HURRICANE CENTER MIAMI FL EP182026
200 AM PDT FRI OCT 09 2026
SATELLITE IMAGERY INDICATES THAT RACHEL'S CONVECTIVE ORGANIZATION
REMAINS LIMITED, WITH THE DEEPEST CONVECTION CONFINED TO THE
NORTHERN SEMICIRCLE. THE LATEST SUBJECTIVE DVORAK INTENSITY
ESTIMATE FROM TAFB WAS T3.0/45 KT, WHICH IS IN GOOD AGREEMENT WITH
THE LATEST OBJECTIVE ESTIMATES FROM UW-CIMSS. GIVEN THESE DATA AND
THE LIMITED CONVECTIVE ORGANIZATION, THE INITIAL INTENSITY IS
LOWERED TO 45 KT.
RACHEL HAS BEGUN ITS ANTICIPATED NORTHEASTWARD TURN OVER THE PAST
SEVERAL HOURS, WITH AN INITIAL MOTION ESTIMATED AT 045/3 KT. A
NORTHEASTWARD MOTION WITH A SIGNIFICANT INCREASE IN FORWARD SPEED
IS EXPECTED DURING THE NEXT COUPLE OF DAYS AS THE CYCLONE
INTERACTS WITH A DEEPENING MID- TO UPPER-LEVEL TROUGH OVER THE
WESTERN UNITED STATES. TRACK GUIDANCE REMAINS IN GOOD AGREEMENT
AND DEPICTS RACHEL MOVING ASHORE OVER THE NORTHERN BAJA CALIFORNIA
PENINSULA LATE SATURDAY BEFORE CONTINUING NORTHEASTWARD INTO THE
SOUTHWESTERN UNITED STATES ON SUNDAY. THE LATEST NHC TRACK
FORECAST IS LARGELY UNCHANGED FROM THE PREVIOUS PREDICTION AND
LIES CLOSE TO THE HCCA AND GDMI AIDS.
DESPITE THE VERY DRY AND STABLE AIR AND RELATIVELY COOL SEA SURFACE
TEMPERATURES ALONG THE FORECAST TRACK, SOME OF THE DYNAMICAL
GUIDANCE SUGGESTS THAT RACHEL COULD MAINTAIN TROPICAL STORM STRENGTH
THROUGH LANDFALL THIS WEEKEND. AS RACHEL ACCELERATES NORTHEASTWARD
AND INTERACTS WITH THE DEEPENING TROUGH, INCREASING UPPER-LEVEL
FORCING AND IMPROVING MID-LEVEL MOISTURE COULD SUPPORT INTERMITTENT
BURSTS OF DEEP CONVECTION. ALTHOUGH THIS INTERACTION WILL ALSO
RESULT IN A SIGNIFICANT INCREASE IN VERTICAL WIND SHEAR, WHICH
SHOULD FURTHER DISRUPT THE CYCLONE'S TROPICAL STRUCTURE, SOME
STRENGTHENING IS POSSIBLE DURING THE NEXT 24 TO 36 HOURS. THE LATEST
NHC INTENSITY FORECAST SHOWS RACHEL REACHING 50 KT IN 36 H BEFORE
WEAKENING AS IT MOVES INLAND. RACHEL IS EXPECTED TO BECOME
POST-TROPICAL OVER THE SOUTHWESTERN UNITED STATES BY 60 H AND
DISSIPATE SHORTLY THEREAFTER. THE LATEST NHC INTENSITY FORECAST IS
SIMILAR TO THE PREVIOUS PREDICTION AND LIES NEAR THE MIDDLE TO UPPER
END OF THE GUIDANCE ENVELOPE. GIVEN THE POTENTIAL FOR
TROPICAL-STORM-FORCE WINDS ALONG PORTIONS OF NORTHERN BAJA
CALIFORNIA THIS WEEKEND, A TROPICAL STORM WATCH WILL LIKELY BE
REQUIRED FOR PORTIONS OF THE NORTHERN BAJA CALIFORNIA PENINSULA
WILL BE LIKELY LATER TODAY.
KEY MESSAGES:
1. RACHEL IS EXPECTED TO APPROACH THE COAST OF NORTHERN BAJA
CALIFORNIA, MEXICO, AND THE NORTHERN GULF OF CALIFORNIA AT TROPICAL
STORM STRENGTH OVER THE WEEKEND, AND A TROPICAL STORM WATCH COULD
BE REQUIRED FOR A PORTION OF THIS AREA LATER TODAY.
2. STRONG GUSTY WINDS ASSOCIATED WITH THE REMNANTS OF RACHEL ARE
EXPECTED TO SPREAD OVER INTERIOR PORTIONS OF THE SOUTHWEST UNITED
STATES, ESPECIALLY IN AREAS OF HIGHER TERRAIN, FROM THIS WEEKEND
INTO EARLY NEXT WEEK.
3. RACHEL AND THE MOISTURE ASSOCIATED WITH THE SYSTEM WILL SPREAD
OVER PORTIONS OF THE SOUTHWEST UNITED STATES AND NORTHERN BAJA
CALIFORNIA PENINSULA THROUGH THIS WEEKEND. THIS WILL LEAD TO
INCREASING COVERAGE OF RAINFALL AND THE POTENTIAL FOR FLASH AND
URBAN FLOODING.
4. SWELLS PARTLY GENERATED BY RACHEL WILL CONTINUE TO BUILD ALONG
THE COAST OF SOUTHERN CALIFORNIA AND NORTHERN BAJA CALIFORNIA.
THESE SWELLS ARE LIKELY TO CAUSE LIFE-THREATENING SURF AND RIP
CURRENT CONDITIONS, AS WELL AS MINOR TO MODERATE COASTAL FLOODING,
THROUGH EARLY NEXT WEEK. PLEASE CONSULT PRODUCTS FROM YOUR LOCAL
WEATHER OFFICE.
FORECAST POSITIONS AND MAX WINDS
INIT 09/0900Z 22.7N 124.9W 45 KT 50 MPH
12H 09/1800Z 23.0N 124.4W 40 KT 45 MPH
24H 10/0600Z 24.1N 122.4W 45 KT 50 MPH
36H 10/1800Z 26.5N 119.3W 50 KT 60 MPH
48H 11/0600Z 30.8N 116.5W 45 KT 50 MPH
60H 11/1800Z 35.3N 114.2W 35 KT 40 MPH...POST-TROP/INLAND
72H 12/0600Z...DISSIPATED
FORECASTER GIBBS
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