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Hurricane Douglas Forecast Discussion Number 9
2020-07-22 16:57:08| National Hurricane Center (East Pacific)
Issued at 500 AM HST Wed Jul 22 2020 000 WTPZ43 KNHC 221456 TCDEP3 Hurricane Douglas Discussion Number 9 NWS National Hurricane Center Miami FL EP082020 500 AM HST Wed Jul 22 2020 Douglas has resumed strengthening, after remaining steady state for almost 24 hours. The system has developed a ragged eye during the past couple of hours, although the cirrus from the inner-core convection has been obscuring that feature somewhat. There is a wide range among the satellite intensity estimates--between 55 kt and 77 kt--and the latest objective guidance is right at the hurricane threshold. Therefore, Douglas has been upgraded to a 65-kt hurricane, the first of the 2020 eastern Pacific season. During the period of reliable records, this is the 4th latest date on which the first hurricane of the season has formed. Douglas continues to move westward, or 265/13 kt, due south of a mid-level ridge which extends from the Baja California peninsula to 140W. This ridge is not expected to change much in strength or position in the coming days, and Douglas is therefore expected to move westward or west-northwestward, gradually gaining latitude, during the entire forecast period. There is very little spread among the track models, although the new suite of models is a little bit faster compared to the previous forecast. The updated NHC forecast has been adjusted accordingly, although it should be noted that the overall forecast path has changed very little. With Douglas's improved structure, low shear and warm sea surface temperatures (28-29C) should support further strengthening during the next 36 hours or so. There's still a significant chance of rapid intensification during that period, with the GFS- and ECWMF-based SHIPS RI guidance both over 50 percent. After that time, oceanic heat content values fall below zero along Douglas's forecast track, and it is likely that the hurricane would begin to gradually weaken, although not considerably so since vertical shear is not expected to increase until about day 4. SHIPS, HCCA, and the Florida State Superensemble are in very good agreement, especially during the first part of the forecast period, and so the NHC intensity forecast closely follows those solutions. This new forecast shows a slightly higher peak intensity compared to previous forecasts. Key Messages: 1. Douglas is expected to move near or over portions of the Hawaiian Islands this weekend, and there is an increasing chance that strong winds and heavy rainfall could affect portions of the state beginning on Sunday. Interests on the Hawaiian Islands should continue to monitor the progress of Douglas. FORECAST POSITIONS AND MAX WINDS INIT 22/1500Z 11.8N 129.5W 65 KT 75 MPH 12H 23/0000Z 12.0N 131.4W 75 KT 85 MPH 24H 23/1200Z 13.1N 134.1W 85 KT 100 MPH 36H 24/0000Z 14.4N 137.0W 95 KT 110 MPH 48H 24/1200Z 15.7N 140.0W 90 KT 105 MPH 60H 25/0000Z 17.0N 143.0W 80 KT 90 MPH 72H 25/1200Z 18.0N 146.1W 70 KT 80 MPH 96H 26/1200Z 19.0N 152.0W 60 KT 70 MPH 120H 27/1200Z 20.0N 158.0W 50 KT 60 MPH $$ Forecaster Berg
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