At 11:00 a.m., Oct. 15, 2015, Nora has given in to persistent and debilitating southwesterly shear, and visible satellite imagery indicates that the low-level circulation is no longer identifiable. Since the cyclone center has dissipated, and shear will remain sufficiently strong to preclude redevelopment, the Central Pacific Hurricane Center has stopped issuing advisories on the remnants of Nora.
At 5:00 a.m., the center of Tropical Depression Nora was located about 425 miles southeast of Hilo.
The depression is moving toward the west near 5 mph. A turn toward the northwest is expected today with a shift back toward the west anticipated on Thursday.
Maximum sustained winds are near 35 mph with higher gusts. Weakening is expected over the next couple of days with Nora expected to become a post-tropical remnant low later today.
The estimated minimum central pressure is 1004 mb.
Surf: Swells generated by Nora will produce hazardous surf along the southeast facing shores of Hawaii Island through Thursday evening.Discussion:
Tropical Depression Nora remains poorly organized this morning with infrared satellite imagery continuing to depict an exposed low level circulation center. Convection continues to pulse to the northeast of the LLCC, but is struggling to hold together given the strong southwesterly vertical wind shear.
Nora’s motion has been erratic overnight due to the pulsing of deep convection to the northeast of the LLCC. Nora is currently being steered off to the west by the low level trade wind flow. This motion is expected to be temporary as the approach of a large upper level trough and forcing from the right rear quad of an upper level jet will likely allow enough convection to pulse over the system through Thursday morning to place Nora on a more northwestward track.
Once the influence of the upper dynamics is lost, Nora is expected to get caught up within the trade wind flow once again, tracking generally westward through dissipation Friday night or Saturday.
The official CPHC forecast track has been shifted to the left of the guidance envelope and the previous official forecast track once again through 36 hours due to the initial
Nora is expected to slowly and steadily weaken over the next several days as persistent vertical wind shear of 35 to 40 knots as indicated by SHIPS guidance will likely keep the LLCC devoid of deep convection. This in combination with the mid-level dry air evident in water vapor imagery wrapping around the entire system will negate any positive contribution from warm sea surface temperatures of around 28 degrees C. As a result, Nora is expected to become a post-tropical remnant low later today with the system dissipating by Friday night or Saturday, if not sooner.