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Hurricane Felicia Forecast Discussion Number 14
2021-07-17 16:44:43| National Hurricane Center (East Pacific)
Issued at 500 AM HST Sat Jul 17 2021 000 WTPZ41 KNHC 171444 TCDEP1 Hurricane Felicia Discussion Number 14 NWS National Hurricane Center Miami FL EP062021 500 AM HST Sat Jul 17 2021 Felicia provided another surprise early this morning, with a ring of very cold cloud tops (
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Tropical Depression Seven-E Forecast Discussion Number 1
2021-07-17 16:40:08| Tropical Depression LIDIA
Issued at 900 AM MDT Sat Jul 17 2021
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Hurricane Felicia Forecast Discussion Number 13
2021-07-17 11:00:08| National Hurricane Center (East Pacific)
Issued at 1100 PM HST Fri Jul 16 2021 000 WTPZ41 KNHC 170859 TCDEP1 Hurricane Felicia Discussion Number 13 NWS National Hurricane Center Miami FL EP062021 1100 PM HST Fri Jul 16 2021 Felicia remains an impressively compact major hurricane on satellite imagery tonight. The storm possesses a circular, clear, and warm (10-15 C) eye surrounded by an equally symmetrical central dense overcast (CDO) with cloud top temperatures colder than -70 C. In addition, a 0535 UTC GMI microwave pass showed a singular closed eyewall, with only limited outer banding outside of the inner core. The 0600 UTC subjective Dvorak satellite estimates from TAFB and SAB were T6.0/115 kt and T5.5/102 kt respectively, while the UW-CIMSS ADT objective estimate was holding steady at T5.7/107 kt. Since that time, cloud top temperatures surrounding the eye have cooled a bit more during the diurnal max, so the initial intensity is held at 115 kt, in agreement with the higher TAFB estimate. The hurricane has maintained more of a west-southwest motion over the past 6-12 hours at 255/8 kt. This motion is expected to gradually bend back westward or west-northwestward over the weekend into early next week as a narrow mid-level ridge axis shifts back to the north-northeast of Felicia. In the latter part of the forecast period, a stronger deep-layer ridge north of Hawaii is expected to become the primary steering feature, leading to a Felicia turning back west-southwestward with gradual acceleration. The track guidance has shifted a tad further north early on, and has continued to speed up the forward motion near the end of the forecast period. The latest NHC track forecast has been adjusted a little more poleward in the first 60 hours, closer to the HCCA and TVCE consensus aids, and is faster after 72 hours. The forecast track still lies roughly between the previous forecast and the aforementioned track consensus aids. Felicia currently has the structural characteristics of an annular hurricane, featuring a warm eye and cold circular CDO with little additional banding beyond the eyewall. Even though sea-surface temperatures (SSTs) slowly decrease over the next 36 hours as Felicia remains embedded in a dry mid-level relative humidity environment, the modest easterly vertical wind shear (around 5-kt) forecast over the cyclone will likely prevent dry-air entrainment that could disrupt the stable eyewall structure. Thus, the intensity forecast for the first 36-48 hours remains above the majority of the guidance and it would not be surprising to see Felicia maintain its category 4 intensity longer than forecasted in the short-term. After 60 hours, the ECMWF-SHIPS guidance shows a sharp increase in northwesterly vertical winds shear as the hurricane tracks along the 26 C SST isotherm. These more unfavorable environmental conditions will likely lead to significant disruption of Felicia's tiny inner core. The weakening rate has been increased a bit more in the latter portion of the latest NHC intensity forecast, falling near the mean of the intensity guidance and HCCA consensus aid by the end of the forecast period. FORECAST POSITIONS AND MAX WINDS INIT 17/0900Z 14.5N 123.9W 115 KT 130 MPH 12H 17/1800Z 14.6N 125.0W 110 KT 125 MPH 24H 18/0600Z 14.9N 126.8W 105 KT 120 MPH 36H 18/1800Z 15.3N 128.7W 100 KT 115 MPH 48H 19/0600Z 15.7N 130.6W 90 KT 105 MPH 60H 19/1800Z 15.8N 132.6W 80 KT 90 MPH 72H 20/0600Z 15.6N 134.9W 65 KT 75 MPH 96H 21/0600Z 14.7N 140.0W 50 KT 60 MPH 120H 22/0600Z 13.8N 145.1W 40 KT 45 MPH $$ Forecaster Papin/Beven
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Hurricane Felicia Forecast Discussion Number 12
2021-07-17 04:32:32| National Hurricane Center (East Pacific)
Issued at 500 PM HST Fri Jul 16 2021 000 WTPZ41 KNHC 170232 TCDEP1 Hurricane Felicia Discussion Number 12 NWS National Hurricane Center Miami FL EP062021 500 PM HST Fri Jul 16 2021 Felicia continues to exhibit characteristics of a classic major hurricane. The eye remains clear while the CDO is symmetrical with uniform cold cloud tops surrounding the center. The latest Dvorak T-numbers from TAFB and SAB support keeping the initial intensity at 115 kt for this advisory. Felicia is a small hurricane, and recent ASCAT overpasses showed that the tropical-storm-force winds extend only about 40-50 n mi from the center. Since earlier this afternoon, the hurricane has been moving south of due west, or 260/08 kt. A strong ridge to the north of the Felicia is expected to maintain it on a generally westward motion for the next several days. Late in the forecast period, the model guidance has trended toward a slightly faster forward motion. The latest NHC forecast track is close to the previous one through 72 h, but now lies in between the previous forecast and the track consensus guidance thereafter. Felicia is expected to move over gradually decreasing SSTs over the next few days which should induce a slow weakening trend beginning later tonight or on Saturday. Although the hurricane is surrounded by dry air, it is maintaining an annular structure while it is expected to remain in an environment of low vertical wind shear for at least a few more days. These factors may prevent this dry air from entraining into the cyclone's circulation for some time. Because of this, the latest NHC intensity prediction remains on the high end of the guidance for the entire forecast period, with the main factor contributing to weakening being the cooler SSTs. FORECAST POSITIONS AND MAX WINDS INIT 17/0300Z 14.8N 123.2W 115 KT 130 MPH 12H 17/1200Z 14.6N 124.5W 110 KT 125 MPH 24H 18/0000Z 14.7N 126.1W 100 KT 115 MPH 36H 18/1200Z 15.1N 128.0W 95 KT 110 MPH 48H 19/0000Z 15.4N 129.9W 85 KT 100 MPH 60H 19/1200Z 15.5N 131.9W 80 KT 90 MPH 72H 20/0000Z 15.5N 134.0W 70 KT 80 MPH 96H 21/0000Z 14.7N 138.2W 60 KT 70 MPH 120H 22/0000Z 13.9N 143.2W 50 KT 60 MPH $$ Forecaster Latto
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Hurricane Felicia Forecast Discussion Number 10
2021-07-16 16:52:52| National Hurricane Center (East Pacific)
Issued at 800 AM PDT Fri Jul 16 2021 000 WTPZ41 KNHC 161452 CCA TCDEP1 Hurricane Felicia Discussion Number 10...Corrected NWS National Hurricane Center Miami FL EP062021 800 AM PDT Fri Jul 16 2021 Corrected 24-hour forecast position Compact Hurricane Felicia has continued to rapidly strengthen this morning with a well-defined, warm (>15C) clear eye now evident in infrared satellite imagery. However, the convective cloud tops surrounding the eye have warmed by almost 10 deg C during the past several hours, and a 1022Z ATMS microwave satellite pass showed the inner core convection a little less organized. Subjective satellite intensity estimates from TAFB and SAB were a consensus T6.0/115 kt and objective estimates from UW-CIMSS ADT over the past couple of hours have averaged T5.7/105 kt. The initial intensity is raised to 110 kt, and just below category 4 strength, for this advisory based on a blend of the various satellite intensity estimates and the slightly degraded aforementioned convective features. Felicia is moving west-southwestward or 255/07 kt. Strong deep-layer ridging to the north of the hurricane is expected to keep Felicia moving west-southwestward for the next 12-24 h. Thereafter, the global and regional models all show the ridge relaxing somewhat, which should allow Felicia to move more westward in the 24-120-hour forecast period. The new NHC track forecast is essentially on top of and just an update of the previous advisory track, and lies near the middle of the tightly packed simple and corrected consensus models TVCE, GFEX, and NOAA-HCCA. Some additional slight strengthening could occur this morning due to low vertical shear and warm SSTs conditions, with Felicia briefly becoming a category 4 hurricane. However, the warm water beneath the powerful hurricane isn't very deep as indicated by upper-ocean heat content values currently only around 5 units, which suggests that cold upwelling could begin at any time during the next 12 hours. Ocean heat content values are forecast to remain below 10 units from 24-96 hours, and decreasing to less than zero thereafter. Thus, slow weakening is forecast to begin by 24 h and continue through the remainder of the forecast period despite the favorable low (
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