ZCZC MIATCDEP1 ALL TTAA00 KNHC DDHHMM RRA TROPICAL STORM AMANDA DISCUSSION NUMBER 4...RETRANSMITTED NWS NATIONAL HURRICANE CENTER MIAMI FL EP012014 800 AM PDT FRI MAY 23 2014 Convection has been gradually filling in near the center and taking on a more pronounced banding structure during the past few hours. Dvorak estimates from TAFB and SAB were T2.0/30 kt at 1200 UTC, but the most recent UW-CIMSS ADT estimates are running around 40 kt. In addition, recent AMSU intensity estimates yielded 38 kt and 44 kt. Based on the higher objective numbers, and the overall increase in convective organization since 1200 UTC, the depression is being upgraded to Tropical Storm Amanda at this time. The initial intensity is set at 35 kt based on a consensus of the subjective and objective numbers. Amanda's initial motion is a slow 295/4 kt. The storm is located to the southwest of a fairly weak mid-level anticyclone over central Mexico and to the south of a large deep-layer low over southern California. The anticyclone is forecast to weaken during the next couple of days, while the deep-layer low slides almost due eastward across the southwestern U.S. As a result, Amanda is expected to remain in weak steering flow, and its motion should remain less than 5 kt during the next 5 days. Amanda is now expected to turn northward by day 5 due to mid-level ridging redeveloping over Mexico and a mid-level low forming near 130W. The GFS has had the most dramatic shift in track since yesterday and now shows Amanda turning northward by the end of the forecast period. The updated NHC forecast has been shifted a bit to the right of the previous one now that there is a little more agreement among the models on a northward turn. Amanda is expected to remain in a relatively light-shear environment for the next 3 days or so, and therefore at least gradual strengthening is anticipated. Although upwelling of cold water could be a concern due to Amanda's slow forecast motion, upper ocean heat content is expected to increase along the cyclone's path. Due to these favorable conditions, the SHIPS RI index still supports a significant potential (about a 50 percent chance of a 25-kt increase over the next 24 hours) of rapid intensification. All of the models have been trending toward a higher peak intensity, led by the SHIPS and GFDL, which both make Amanda a hurricane by 48 hours. The new NHC forecast is not quite that aggressive, but it does now show Amanda reaching hurricane strength in about 3 days or so. FORECAST POSITIONS AND MAX WINDS INIT 23/1500Z 10.9N 108.4W 35 KT 40 MPH 12H 24/0000Z 11.1N 108.9W 40 KT 45 MPH 24H 24/1200Z 11.5N 109.7W 45 KT 50 MPH 36H 25/0000Z 11.7N 110.3W 50 KT 60 MPH 48H 25/1200Z 11.9N 110.8W 55 KT 65 MPH 72H 26/1200Z 12.5N 111.5W 65 KT 75 MPH 96H 27/1200Z 13.5N 112.0W 65 KT 75 MPH 120H 28/1200Z 15.0N 112.0W 60 KT 70 MPH $$ Forecaster Berg NNNN