ZCZC HFOTCDCP4 ALL TTAA00 PHFO DDHHMM Tropical Storm Norman Discussion Number 44 NWS Central Pacific Hurricane Center Honolulu HI EP162018 500 PM HST Fri Sep 07 2018 The exposed low-level circulation center of Norman has been evident in visible satellite imagery through the day, with convection persisting only in the northern semicircle. Crews from the 53rd Weather Reconnaissance Squadron were flying aircraft from California to Hawaii this morning, in order to prepare for future missions into and around Hurricane Olivia. Unexpectedly, one of the aircraft was able to briefly make a penetration into Norman. This data indicated that Norman was likely a little stronger than analyzed for the last advisory. Meanwhile, a 2001Z ASCAT pass sampled Norman's eastern semicircle, and indicated winds of at least 55 kt, with wind radii somewhat larger than previously indicated. Based primarily on the above data, the initial intensity for this advisory will be held at 60 kt. The initial motion estimate for this advisory is 340/9 kt. Norman is moving toward the north-northwest between a deep-layer ridge centered to the east, and a longwave trough to the northwest. Although there are some wiggles in the forecast track, little overall change to this pattern is expected the next couple of days, with Norman generally moving toward the north. The updated track forecast lies close to HCCA and TVCE, and although it was shifted to the right again, it required less changes than the previous two forecast cycles. Vertical wind shear estimated to be 40-50 kt will persist for the next 48 hours, with some decrease thereafter. With lowering SSTs along the forecast track, Norman is expected to be over sub 25C degree water when the shear eases. The combined effects will cause Norman to weaken to a remnant low by day 3 before dissipating by day 5. The official intensity forecast delays dissipation as compared to the statistical guidance, and is more in line with the dynamical model guidance. FORECAST POSITIONS AND MAX WINDS INIT 08/0300Z 25.0N 153.3W 60 KT 70 MPH 12H 08/1200Z 26.2N 153.9W 55 KT 65 MPH 24H 09/0000Z 27.7N 154.7W 50 KT 60 MPH 36H 09/1200Z 29.4N 154.7W 45 KT 50 MPH 48H 10/0000Z 31.0N 154.4W 35 KT 40 MPH 72H 11/0000Z 33.9N 154.6W 30 KT 35 MPH...POST-TROP/REMNT LOW 96H 12/0000Z 35.5N 156.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 13/0000Z...DISSIPATED $$ Forecaster Birchard NNNN
Alternate Formats
About Alternates -
E-Mail Advisories -
RSS Feeds
Cyclone Forecasts
Latest Advisory -
Past Advisories -
About Advisories
Marine Forecasts
Latest Products -
About Marine Products
Tools & Data
Satellite Imagery -
US Weather Radar -
Aircraft Recon -
Local Data Archive -
Forecast Verification -
Deadliest/Costliest/Most Intense
Learn About Hurricanes
Storm Names
Wind Scale -
Prepare -
Climatology -
NHC Glossary -
NHC Acronyms -
Frequently Asked Questions -
AOML Hurricane-Research Division
About Us
About NHC -
Mission/Vision -
Other NCEP Centers -
NHC Staff -
Visitor Information -
NHC Library
NOAA/
National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
11691 SW 17th Street
Miami, Florida, 33165-2149 USA
nhcwebmaster@noaa.gov
Disclaimer
Privacy Policy
Credits
About Us
Glossary
Career Opportunities
Page last modified: Thursday, 08-Aug-2019 14:27:42 UTC