Daniel becomes a hurricane, has likely peaked; Invest 97E nearly a TD
Daniel continued to strengthen overnight and became the 2012 Pacific hurricane season's third hurricane. As of the latest advisory from the National Hurricane Center, Daniel was located at 14.9 °N 119.2 °W, or about 820 miles southwest of the southern tip of Baja California. Maximum sustained winds had increased to 85 mph with higher gusts, making it a Category 1 hurricane on the Saffir-Simpson Hurricane Wind Scale. The minimum barometric pressure down to 980 millibars, and the storm was moving towards the west at 13 mph. As of the 18Z ATCF file update, maximum sustained winds were up to 90 mph and the minimum barometric pressure was down to 977 millibars. Visible satellite loops reveal a well-formed hurricane with a large, curved band on the southern side of the storm and deep convection around an intermittent eye. Satellite-derived intensity estimates from NESDIS' Satellite Analysis Branch (SAB) were 5.0/90 knots and 4.8/85 knots from UW-CIMSS ADT. Daniel has likely peaked.
Figure 1. Afternoon visible satellite imagery of Hurricane Daniel.
The forecast for Daniel
Daniel has begun to level off in intensity as it begins to interact with the large mass of dry air to its north. In addition, Sea Surface Temperatures have begun to drop below 26 °C, the value needed to sustained a tropical cyclone. While wind shear should stay low through most of the forecast period, a combination of the dry environment ahead and significantly cooler Sea Surface Temperatures should induce rapid weakening of Daniel by tomorrow. A majority of the computer intensity models show the cyclone dropping below hurricane status within 36 hours and below tropical storm status by 84 hours; this is depicted by the National Hurricane Center forecast. Daniel should become a remnant low by 96-120 hours out.
While quickly dying, Daniel should remain on a due westerly course well away from the coastline of Mexico. This is a higher-than-average forecast due to the superb model track consensus. If Daniel remains a tropical cyclone through 120 hours, it could impact Hawaii in the form of gusty winds, heavy rainfall, and high surf, but the storm is not expected to make a direct landfall on the island and should instead pass south of it.
...FORECAST POSITIONS AND MAX WINDS...
INIT 07/1800Z 14.6N 119.6W 80 KT 90 MPH
12H 08/0600Z 15.2N 121.0W 75 KT 85 MPH
24H 08/1800Z 15.4N 123.5W 65 KT 75 MPH
36H 09/0600Z 15.7N 126.2W 60 KT 70 MPH
48H 09/1800Z 15.9N 129.1W 55 KT 65 MPH
72H 10/1800Z 16.3N 135.4W 40 KT 45 MPH
96H 11/1800Z 16.5N 142.0W 30 KT 35 MPH
120H 12/1800Z 16.8N 148.6W 25 KT 30 MPH...REMNT LOW
97E close to TD status
A well-defined area of low pressure located roughly 500 miles south of Acapulco, Mexico is very nearly a tropical depression this afternoon. Visible satellite loops reveal a pronounced low-level spin, and shower and thunderstorm activity associated with the invest has been consolidating near the center over the past 24 hours. The latest National Hurricane Center Tropical Weather Outlook gave 97E a high chance, Near 100%, of becoming a tropical cyclone over the next 48 hours, stating that the disturbance has organized and if this trend continues, advisories will be initiated later today. Given its current satellite appearance and satellite-derived intensity estimates of 1.5/1.5 from NESDIS' Satellite Analysis Branch, I believe Invest 97E has attained tropical depression status at this time.
Figure 2. Afternoon visible satellite imagery of Invest 97E.
The forecast for 97E
Invest 97E lies in an environment very conducive for additional organization. Wind shear is below 5 knots, Sea Surface Temperatures are near 29 °C, and Relative Humidity values are near 75%, indicative of a very moist environment. Wind shear is expected to stay conducive for intensification through 120 hours, but the system may begin to struggle somewhat with dry air by 96 hours out as it approaches the same mass of dry air that should act to weaken Hurricane Daniel. Sea Surface Temperatures will drop below 26 °C by that time as well. Until then however, there is no reason to think that once 97E becomes a tropical storm and builds an eyewall, it won't rapidly intensify. A majority of the model intensity guidance foresees 97E becoming a Category 1 hurricane at peak. Given the environment, it is believed that the system may get significantly stronger, and may become a major hurricane before weakening.
As for track, it is pretty much as straightforward as it was for Daniel. Invest 97E is rounding the southern periphery of a large and strong area of high pressure located over the Central US Plains. This will prevent the storm from recurving eastward and should keep the cyclone well away from the Mexican coastline.
The Atlantic is quiet
The Atlantic is quiet today with no areas of concern for development. There are some healthy tropical waves in the East Atlantic, but all of them are embedded within the Intertropical Convergence Zone and just south of a large mass of Saharan Air Layer (SAL). None of the global models show development over the next week to 10 days, and we will likely remain quiet until August.