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Tropical Storm Flossie - July 29, 2013

Amateur radio operators throughout Hawaii responded to Tropical Storm Flossie that arrived in Hawaiian waters on Monday July 29, 2013.

Activities are chronicled here. It's not a question of "If", it's a question of "When".

Enjoy, and feel free to drop me an e-mail if you have any questions.

Paul Amagata WH6FM, Ron Hashiro AH6RH, Clem Jung KH7HO contributed to this report.

Amateur radio operators responded to Tropical Storm Flossie as the Central Pacific Hurricane Center issued Advisory 12 on Saturday, July 27, 2013 at 11:00 am HST announcing that Flossie had crossed Longitude 140 into the Central Pacific hurricane region. Flossie approached from the east, heading steadily almost due west at 20 MPH.

Plans were underway with the amateur radio leadership of NWS SKYWARN and Hawaii State Civil Defense RACES the night before to coordinate a joint net on the state-wide VHF Repeater system for passing storm information to the National Weather Service Honolulu Forecast office at HIG Building, University of Hawaii at Manoa campus. The repeaters of DEM RACES (Oahu County) and SCD were linked using ALL-STAR VOIP linking to create a eight node repeater cluster of both State-wide and around-the-island repeaters for Oahu for reporting and monitoring purposes.

The repeaters linked from State Civil Defense

  • 147.02+ PL 103.5, Mt Haleakala, Maui 9,769 ft
  • 147.04+ no PL, Mauna Loa, Big Island 8,200 ft
  • 147.04+ PL 103.5, Lihue, Kauai
  • 147.06+ PL 103.5, Diamond Head, Oahu
  • 444.325+ PL 103.5, Waimanalo, Oahu
  • 444.350+ PL 103.5, Diamond Head, Oahu

and Department of Emergency Management, Oahu County

  • 146.76- no PL, Mokuleia, Oahu
  • 146.98- PL 88.5, Frank Fasi Municipal Building, Oahu

An SKYWARN update net was planned for Sunday at 7:00 pm, ahead of the regular weekly ARES EMCOMM Practice net. The latest update from the NWS plus the latest coordination information was slated for the net.

SKWARN operations began at 10:00 am Monday July 29, 2013 about two hours after the Big Island began experiencing the storm effects of Flossie. TS Flossie Advisory Number 20 positioned Flossie at 65 miles NNE of Hilo with winds of 40 MPH.

The NWS SKYWARN operations remained active until it was closed at 9:58 pm.


Net operations started at 11:00 am Monday. Net Control Stations were: Tom KH6BLA, Bart KH7C, Jack KH6DQ, Odell WH6EAO, Clem KH7HO. WH6EAO handled his first net at the NWS with Tom assisting from home. Odell did a superb first-time job as NCS, asking the stations to clarify their report to make it of value to the NWS meteorologists.

The meteorologists requested reports of heavy rainfall to confirm the cloud information they were seeing on the NEXRAD radar. Amateur radio reports on the SKYWARN nets were supplemented with messages relayed via cell phone calls, text messages and Facebook.

This was the first tropical cyclone in Hawaiian waters that encountered the massive volcanoes on the Big Island. As predicted, the mass of the mountains disrupted the circular motion of the storm causing a portion to separate and head around South Point. It also deflected the main portion to head north where it encountered the mass of Mt. Haleakala on Maui and headed further north. The combined action of these three volcanoes caused the moisture to deflect upwards, forming thunderhead clouds up to an estimated 60,000 feet. The cold temperatures caused the moisture to form ice and rain, which fell as heavy downpours on the island of Maui and Molokai.

Harvey AH6JA reported light rain in Hilo.

A number of stations on Maui reported lightning, heavy rains and power outages. WH6CDT, KH6HHG, AH7RC, KH6UU, NH6XO.

Cedric KH6CED on Lanai confirmed the passage of a squall line containing heavy rains and lightning. Cedric estimated between half-inch and one inch of rainfall per hour.

Sherman WH6IT on Molokai reported heavy rain and power outages as the main portion remained off the north coast of Molokai dumping massive rains.

Jeff AH6IX provided real-time reporting from the Makapuu Lookout. The NWS was concerned that the cloud cell contained heavy rains, lightning, hail and waterspouts. He was able to confirm movement of a lightning and bearing cloud cell as it moved through the Molokai Channel. The cell moved 13 miles in 35 minutes and dissipated just short of Kailua Beach That was confirmed via Facebook by a resident in the Kailua area confirming that only light rain was falling and that the lightning which stepped up from once every 3 minutes to once every 45 seconds had stopped.

Chris NH7QH reported lightning visible and thunder audible in the Pearl Harbor/Aiea area.

The squall line from Lanai arrived on Oahu about 11:00 pm. It brought rain, but not the threatening heavy rain seen on Molokai and Maui.

Hawaii State

State CD amateur radio operations monitored the NWS SKYWARN net remotely from work and home ready to provide additional assistance and relays of messages from SKYWARN to the SCD EOC. The operations started at 11:00 am, and closed at 9:58 pm.

Hawaii County

The Hawaii County Emergency Auxiliary Communications Net began at 6:00 am Monday, July 29, 2013. Net Control West covered the Ka`u to North Kohala districts. Net Control West operated on:

  • VHF: 146.580 Simplex
  • UHF: 443.650+ PL: 100 Repeater 443.475+ PL: 100.0, 443.400+ PL: 100.0
  • HF: 7.090 ~ 7.094 LSB

Net Control East covered Puna to Hamakua Districts. Net Control East operated on:

  • VHF: 146.760 -600khz Offset, 146.760 Simples (Secondary)
  • UHF: N/A
  • HF: 7.090 ~ 7.094 LSB

The only stations expected on the net were:

  • Those associated with served agencies (such as CERTs, Neighborhood Watch teams, evacuation shelters, hospitals, community association, etc).
  • Stations with first-hand knowledge of previously unreported flooding and road obstructions.
  • Stations with first-hand knowledge of Threat to Human Life where 911 could not be contacted.

The priority for handling messages was as follows:

  • Emergency Alert Messaging from Civil Defense to the general public
  • Life Safety from Communities to Civil Defense requiring professional responder notification and follow-up
  • Time Critical Information
  • Routine Reports and Needs
  • No off island stations were accepted in the net.

The Auxiliary Communications Services net remained operational until 11:30 pm when it was closed by Hawaii County Civil Defense. One amateur radio station had a personal weather station which provided timely and accurate weather reports through to the EOC.

The Hawaii Tribune-Herald later reported about 5,000 people were without power at 2:00 pm, from Volcano to Glenwood, Kalapana to Nanawale, and Pawaewa. Service to Mountain View and Kurtistown were previously restored.

Mayor Kenoi addressed the those in EOC including the volunteers with his gratitude and support to all of them for their part in the 4 days worth of activities leading up to and through Tropical Storm Flossie.

Maui County

Oahu County

Kauai County


A reminder: Being prepared is a personal responsibility. Stock up ahead of time, and don't get caught in the mad rush to the store to buy stuff.

A reminder for the general population (and amateur radio operators alike) that the primary means of timely notification of an alert is via the NOAA National Weather Service Weather Alert radios.

Web article

New satellite instrument takes guesswork out of Flossie's nighttime track

NASA Photo

After Action Report

Amateur radio provides timely reports to NWS and EOCs during Tropical Storm Flossie

Bart Aronoff KH7C, Paul Agamata WH6FM, Mel Fukunaga KH6H, Bob Schneider AH6J, Harvey Motomura AH6JA, Clem Jung KH7HO and Ron Hashiro AH6RH contributed to this report.

Amateur radio operators provided timely reports of weather and power outages to the National Weather Service (NWS) forecast office in Honolulu and to the County Emergency Operating Centers (EOCs) in Hawaii when Tropical Storm Flossie pounded parts of Hawaii and Maui counties with heavy rains and lightning.

Tropical Storm Flossie arrived in Hawaiian waters from the east on the morning of Monday July 29, packing winds of 40 mph. The Honolulu Forecast office notified residents through the entire state starting Saturday to prepare for tropical storm conditions with heavy rains and flooding.

The amateur radio leadership organized a joint SKYWARN, ARES and RACES operation using eight VOIP and microwave-linked VHF and UHF repeaters from State Civil Defense (SCD) RACES and the Oahu County Department of Emergency Management (DEM) RACES to serve the NWS, the Central Pacific Hurricane Center (CPHC), State and County governments.

Clem Jung KH7HO opened the SKYWARN Net for Tropical Storm Flossie on Sunday night at 7:00 p.m. HST (July 29 0500z) from the amateur radio station in the NWS Honolulu Forecast office at the University of Hawaii Manoa campus. NWS Warning Meteorologist, Mike Cantin gave a weather report and briefing those checked into the net, projecting the effects of the storm being felt on the Big Island of Hawaii around 8:00 am in the morning. The net concluded with an update that net operations would resume at 10:00 a.m. and the repeaters would remain linked overnight.

The SKYWARN Net reconvened at 10:00 a.m. HST on the All-Star linked repeaters and the 7088 kHz HF frequency. All counties were under a Tropical Storm warning with Flash Flood watch or warnings in effect. The Net Control stations at NWS were Bart Aronoff KH7C, Jack Tsujimura KH6DQ, Odell Ching WH6EAO, and Clem Jung KH7HO. In addition, Carter Davis KH6FV in Kaimuki, Tom Geier KH6BLA in Waikiki and Tad Miura NH7YS on Kauai served as remote NCSes to supplement those at NWS.

During the 12 hours of activation, the net had 67 check-ins and received reports from amateur radio operators from all four counties. Amateur radio operators throughout the state provided the NCSes with reports throughout the state gathered using ham radio, cell phones and social media such as Facebook that were passed to the meteorologists at CPHC. The majority of the traffic was voice messages with only one Fldigi ICS-213 weather report message received.

Harvey Motomura AH6JA and others on east side of the Big Island gave ground observations of rain and lightning conditions supplementing the cloud information visible via the NEXRAD radar and infrared satellite images. Ian Morrison, the NWS SKYWARN Coordinator gave a Tropical Storm Flossie update during the net. As the storm moved westward, others on Maui, Lanai and Oahu provided reports.

The State Civil Defense EOC and the four county EOCs were activated with amateur radio operators monitoring SKYWARN weather reports for EOC traffic while at home or at the EOC. Mel Fukunaga KH6H handled Maui County Civil Defense; Elsie Watanabe WH7BB and Ralph Miranda WH7PD reported to Oahu DEM; and Kevin Bogan AH6QO, Ron Hashiro AH6RH and Larry Sue AH6SP provided coverage for State CD.

Concurrently, the Auxiliary Communication Service amateur radio nets on the Big Island were relaying valued messages between served agencies such as CERT, Neighborhood Watch, American Red Cross shelters and the County EOC. Paul Agamata WH6FM, Bob Schneider AH6J, and several others took turns at Hawaii County CD. Milt Nodacker AH6I and his crew ran net control for CERT operations handling the exchange of messages. Several hundred CERT members were estimated to be active. Agamata noted during the 1:00 pm briefing that Mayor Billy Kenoi took time to address those in EOC including the volunteers with his gratitude and support to all of them for their part in the four days' worth of activities leading up to and through Tropical Storm Flossie.

"The Monday 5:00 am CPHC discussion noted that a shear from the northwest continued to weaken the storm," said Ron Hashiro AH6RH. "As Flossie approached the Big Island, the two massive volcanoes of Mauna Kea and Mauna Loa with summits above 13,600 feet and an upper level shear caused the storm to split in two — with the mid and upper level portion moving south around the Big Island and the lower level portion heading northwest towards the island of Maui. A third volcano, Mt. Haleakala on Maui, further degraded the circular motion of Flossie causing the NWS to downgrade the storm to a tropical disturbance at 4:48 pm."

The SKYWARN net was set to deactivate around 8:00 p.m, however, the weather situation developing over Maui, Lanai, and Molokai islands caused a reevaluation. The volcanoes forced the moist air from Flossie to deflect upwards and raise the tops of the thunderclouds. Clem Jung said that the meteorologists were seeing cloud heights towering near 60,000 feet over Maui. The added vertical motion caused more ice and static electricity to form, which came down over the island of Maui as extra heavy lightning activity. The NEXRAD radar displays showed thunderclouds approaching the Maui County islands that could cause hail, very active lightning and possible tornado development. Reports by the hams of power outages on Maui and lots of lightning, thunder and rain poured into the CPHC. Fukunaga said that the amount of lighting ground strikes in and around Kahului was unbelievable. At 5:57 pm, the CPHC issued a special weather statement advising of rain, dangerous frequent cloud-to-ground lightning and small hail for Maui County. Warning Meteorologist, Mike Cantin, gave an updated weather report on the net.

One of the radars began showing anomalies occurring southwest of Maui and the NWS requested SKYWARN if one of the hams could report the weather and lightning situation. Arch Stewart AH7RC reported that no lightning was occurring in the area of concern. "The forecasters were very happy that they were able to resolve the anomaly with an actual observation" said Bart Aronoff KH7C. Cedric Urpanil KH6CED on Lanai followed up on an NWS request and reported heavy rains of an estimated half to one inch per hour with lightning. The heavy rain and lightning continued along the north side of the island of Molokai as Sherman Napolean Jr WH6IT radioed in the reports of heavy weather and power outages.

As the diminishing storm continued to Oahu, the NWS was concerned about a cloud cell in the Molokai channel between Molokai and Oahu containing heavy rains, hail and possible waterspouts heading to the Windward side estimating the arrival near 9:00 pm. Jeff Sue AH6IX stationed at the lookout at Makapuu Pt on the eastern tip of the island visually confirmed the oncoming lighting activity in the Molokai Channel. Chris Colquhoan NH7QH confirmed the lighting and thunder reports from near Honolulu International Airport. As the cloud traveled 13 miles in 35 minutes, it completely dissipated with only light rain as confirmed through a Facebook report relayed by Ron Hashiro AH6RH. As a result, the Central Pacific Hurricane Center gave SKYWARN the go ahead to close the net at 9:58 p.m. HST.

Overall, the meteorologists at the Central Pacific Hurricane Center appreciated the timely amateur radio reports that validated what they saw on their radars and instruments and as well as the additional real-time information such as power outages that they did not have. "The cooperation and communication between the SKYWARN NCSes and the NWS was fantastic" commented Clem Jung KH7HO. "This success was possible because of the emergency coordinators previously working with the amateur radio community that participated in this net." The amateur radio operators likewise were appreciative of the interaction with the NWS and of the support of Meteorologist In Charge of the Honolulu office Ray Tanabe who is also amateur radio operator WH7IH.

Lessons Learned

The Star-Advertiser Reporting

July 31, 2013

These are links to articles from The Star-Advertiser.

Find out more by contacting:  rhashiro(remove this part)@hawaiiantel.net
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July 31, 2013. Updated: November 15, 2013

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