WTPZ44 KNHC 310237 RRA

TCDEP4



TROPICAL STORM LIDIA DISCUSSION NUMBER   6

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP142017

900 PM MDT WED AUG 30 2017



SATELLITE IMAGES INDICATE THAT THE CIRCULATION, ALTHOUGH BROAD, IS

MORE CONSOLIDATED, AND CONVECTION HAS BECOME MORE CONCENTRATED NEAR

THE CENTER. HOWEVER, THERE IS NO EVIDENCE OF AN INNER CORE AT THIS

TIME. DATA FROM A UNMANNED NASA GLOBAL HAWK AIRCRAFT CURRENTLY IN

THE AREA OF LIDIA, AND OBSERVATIONS FROM THE MEXICAN NAVY AUTOMATIC

WEATHER STATIONS, WERE VERY HELPFUL IN DETERMINING THE STRUCTURE OF

THE CYCLONE. THE BEST ESTIMATE OF THE INITIAL INTENSITY IS 35 KT.



LIDIA IS WITHIN A VERY FAVORABLE ENVIRONMENT OF LOW SHEAR, AND THE

OCEAN IS WARM.  THE ONLY FACTOR AGAINST A HIGHER INTENSIFICATION

RATE APPEARS TO BE THE LARGE SIZE OF THE CYCLONE. THE NHC FORECAST

CALLS FOR GRADUAL STRENGTHENING DURING THE NEXT 12 TO 24 HOURS, AND

LIDIA HAS A CHANCE TO BE NEAR HURRICANE STRENGTH BEFORE THE CYCLONE

BEGINS TO INTERACT WITH THE HIGH TERRAIN OF THE BAJA CALIFORNIA

PENINSULA. AFTER THAT TIME, GRADUAL WEAKENING SHOULD THEN BEGIN.



THE OVERALL CIRCULATION IS STILL MOVING TOWARD THE NORTH-NORTHWEST

OR 345 DEGREES AT 6 KT. LIDIA IS BEING STEERED BY THE FLOW BETWEEN

A WEAK RIDGE OVER MEXICO AND A WEAK CYCLONIC GYRE TO THE WEST. THIS

PATTERN WILL PERSIST, AND THE CYCLONE SHOULD CONTINUE ON THE SAME

GENERAL TRACK FOR THE NEXT 2 DAYS. ONCE THE CYCLONE REACHES THE

CENTRAL PORTION OF BAJA CALIFORNIA PENINSULA, A RIDGE TO THE NORTH

IS FORECAST TO AMPLIFY, AND THIS FLOW PATTERN WILL FORCE A WEAKER

LIDIA ON A MORE WEST-NORTHWEST TRACK TOWARD COLD WATERS.



IT IS IMPORTANT TO EMPHASIZE THAT LIDIA IS A LARGE SYSTEM