000 WTPZ43 KNHC 161451 TCDEP3 Hurricane Kiko Discussion Number 17 NWS National Hurricane Center Miami FL EP132019 800 AM PDT Mon Sep 16 2019 Microwave data and satellite imagery continue to indicate that the core of Kiko is being disrupted. While there is a seemingly favorable outflow pattern, northeasterly shear is undercutting the top layer and preventing the cyclone from having a closed eyewall. Satellite estimates are falling and support a perhaps-generous initial wind speed of 90 kt. The shear is forecast to continue during the next day or so, which should promote further weakening. After that time, the shear could lessen, although the environment overall is hardly very conducive for strengthening, and this scenario would best support little change in intensity. By Friday-Saturday, model guidance does show an increase in shear, so a more notable weakening could occur. The new NHC intensity forecast is reduced from the previous one, following the trend in the guidance, but is a bit above the model consensus. A fair number of models actually show a weaker cyclone, but in a complex environment, I'd rather be conservative in changing the longer-range intensity forecast. There's no significant track change to report with Kiko. The hurricane is moving westward at 4 kt, to the south of a weak mid-level ridge. By 36 hours, another ridge building to the northwest of the hurricane will begin to steer Kiko to the west-southwest. This ridge is then forecast to weaken by 72 hours, while subtropical ridging builds to the north and northeast of the cyclone. This will likely result in a general westward to west-northwestward track through the end of the forecast period. The new forecast track is close to the previous one, on the faster and southern side of the guidance, which has generally been the right place to be with Kiko's track. FORECAST POSITIONS AND MAX WINDS INIT 16/1500Z 17.3N 123.7W 90 KT 105 MPH 12H 17/0000Z 17.3N 124.3W 80 KT 90 MPH 24H 17/1200Z 17.2N 125.1W 70 KT 80 MPH 36H 18/0000Z 16.9N 126.0W 65 KT 75 MPH 48H 18/1200Z 16.7N 127.0W 60 KT 70 MPH 72H 19/1200Z 16.9N 129.1W 60 KT 70 MPH 96H 20/1200Z 17.3N 130.7W 55 KT 65 MPH 120H 21/1200Z 17.3N 132.5W 45 KT 50 MPH $$ Forecaster Blake