ABHW40 PHNL 021800 PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE HONOLULU HI 8 AM HST WED DEC 2 1998 ...AN UPDATE ON HAWAII RAINFALL DURING THE ONGOING LA NINA EPISODE... A MIXED BAG THROUGHOUT THE STATE. INDIVIDUALS IN SOME AREAS MAY FEEL LIKE THE ENHANCED RAINFALL EXPECTED DURING A LA NINA EPISODE IS HERE. OTHERS...ESPECIALLY IN THE LEEWARD AREAS OF THE ISLANDS OF MAUI AND HAWAII...CONTINUE TO SEE BELOW NORMAL RAINFALL. LARGE SCALE TRADE WINDS CONTINUED TO PLAY A DOMINANT ROLE IN THE WEATHER PATTERN OVER THE HAWAIIAN ISLANDS THROUGHOUT THE MONTH. NORMALLY THE MONTH OF NOVEMBER MARKS THE START OF THE COOL SEASON WITH THE ISLAND CHAIN NORMALLY EXPERIENCING THE PASSAGE OF SEVERAL COLD FRONTS OR SHEAR LINES. SUBTROPICAL CYCLONES...OR KONA STORMS...CAN ALSO DEVELOP WEST OF THE ISLANDS TO PRODUCE PROLONGED PERIODS OF HEAVY RAIN. DURING NOVEMBER 1998 ONLY ONE SHEAR LINE (THE REMNANT OF A COLD FRONT) WAS ABLE TO REACH THE ISLAND CHAIN. THE SHEAR LINE STALLED OVER THE ISLAND OF KAUAI AND THE KAUAI CHANNEL ON 11 NOVEMBER BEFORE LIFTING OUT TOWARD THE NORTHEAST. FRAGMENTS OF THIS SHEAR LINE AND SUBSEQUENT SHEAR LINES EMBEDDED WITHIN THE TRADE WINDS HIT THE ISLANDS FROM THE EAST NORTHEAST OVER THE PERIOD FROM 12 NOVEMBER TO 20 NOVEMBER AND CAUSED ENHANCED TRADE SHOWERS...MAINLY OVER THE WINDWARD SECTIONS OF THE ISLANDS. UPPER LEVEL TROUGHS HELPED ENHANCE THE SHOWER ACTIVITY...ESPECIALLY OVER THE ISLANDS OF MAUI AND HAWAII DURING THIS PERIOD. THIS PERIOD OF ENHANCED TRADE WIND SHOWERS HELPED PUSH RAIN TOTALS WELL ABOVE NORMAL ACROSS MOST OF THE WINDWARD SIDE OF THE ISLAND OF HAWAII AND OVER THE INTERIOR SECTIONS OF THE KO'OLAU MOUNTAINS. THE LACK OF COOL SEASON STORMS RESULTED IN BELOW NORMAL RAINFALL TOTALS ACROSS THE LEEWARD AREAS ACROSS THE STATE. THE RAINFALL DEFICIT WAS ESPECIALLY PRONOUNCED OVER THE LEEWARD AREAS OF MAUI WHERE ALL GAGES REPORTED LESS THAN 50 PERCENT OF NORMAL AND IN SOME CASES LESS THAN 20 PERCENT OF NORMAL. BELOW ARE RAINFALL STATISTICS FOR SELECTED LOCATIONS FROM AROUND THE STATE. THE FIRST COLUMN IS THE OBSERVED RAINFALL FOR NOVEMBER. THE SECOND COLUMN HAS THE 30 YEAR AVERAGE FOR THAT LOCATION WHILE THE THIRD COLUMN LISTS THE PERCENT OF AVERAGE RAINFALL FOR THE MONTH OF NOVEMBER. KAUAI NOV AVG %AVG LIHUE 1.90 5.4 35 HANALEI 6.70 12.2 55 HANAPEPE 1.68 3.2 53 OAHU HONOLULU 0.85 3.0 28 MANOA ARBOR. 17.42 13.5 129 WAIAWA 10.91 6.9 158 PUNALUU 4.39 8.0 55 WAIANAE 0.46 2.0 23 WAIALUA 1.78 4.2 42 MOLOKAI KAUNAKAKAI 0.58 1.6 36 LANAI LANAI CITY 1.35 3.8 36 MAUI KAHULUI 1.94 2.6 75 HANA 3.13 8.7 36 KIHEI 0.00 1.5 0 LAHAINALUNA 0.36 2.0 18 WAILUKU 1.80 2.9 62 HAWAII HILO 15.57 14.5 107 GLENWOOD 25.80 17.8 145 LAUPAHOEHOE 14.94 13.6 110 KAMUELA (UPPER) 6.91 5.3 130 PAHALA 1.48 5.5 27 HONAUNAU 1.51 3.6 42 DATA SOURCES: FIRST ORDER CLIMATE NETWORK WEATHER OBSERVATIONS STATIONS OF THE NATIONAL WEATHER SERVICE AT LIHUE, HI, HONOLULU, HI, KAHULUI, HI, AND HILO, HI.. ADDITIONAL DATA WERE TAKEN FROM THE HYDRONET STATE NETWORK OF AUTOMATED RAIN GAGES. DATA COLLECTED IN THE AUTOMATED GAGES ARE NOT CERTIFIED AND INFORMATION USED ABOVE SHOULD BE USED FOR INFORMATION PURPOSES ONLY. KEVIN R. KODAMA, SENIOR SERVICE HYDROLOGIST NATIONAL WEATHER SERVICE FORECAST OFFICE HONOLULU, HAWAII