Guam, 2016

Tropical Storm in Guam, December 22 to 24, 2016

December 22 to 24, 2016 · NWS GUM · 1 event in 1 county or zone

Tropical Storm Nock-ten passed across portions of Micronesia during the last half of |the month.

The toll

Deaths
0
Injuries
0
Property damage
$100,000
Crop damage
$50,000
Events
1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS GUM wrote it up.

Tropical Storm Nock-ten passed across portions of Micronesia during the last half of |the month.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Guam wrote its last area forecast discussion before the first event at Dec 21, 11:00 AM UTC, 3 hours earlier.

Area forecast discussion, Dec 21, 11:00 AM UTC, 3 hours before
Area Forecast Discussion
National Weather Service Tiyan GU
900 PM ChST Wed Dec 21 2016

.Synopsis...
Latest visible satellite data shows mostly cloudy skies with
scattered showers and isolated thunderstorms over Tinian, Saipan
and Rota waters this afternoon. Isolated showers are seen over
Guam waters. Fresh to strong trade winds continue across the
area. Latest buoy readings show seas between 7 and 11 feet this
afternoon.

&&

.Discussion...
A weak tropical disturbance moving through the Marianas brought
scattered showers and a few thunderstorms to Rota, Tinian and
Saipan today. This activity will continue to move westward through
tonight with drier conditions expected Thursday morning. Residual
cloudiness is then expected to remain over the Marianas through
Friday afternoon. Fresh to strong trade winds will continue across
the region through the remainder of the week, becoming moderate to
fresh for the weekend.

&&

.Marine...
Latest buoy data show seas remaining between 7 and 11 feet across
the coastal waters this afternoon. Seas of 8 to 12 feet are
expected to begin to slowly subside tonight, possibly falling
below levels hazardous to operators of small craft over the
weekend. Fresh to strong trade winds will also slowly subside over
the next couple of days, becoming moderate to fresh for the
weekend.

&&

.Tropical systems...
Tropical Depression 30W has formed to the southeast of Yap, near
7N141E. This system is expected to intensify over the next 24
hours, possibly becoming a Tropical Storm late Thursday morning.
30W is forecast to move west-northwestward over the next couple
of days, passing between the islands of Ngulu and Yap, in Yap
State Thursday, near noon. A Tropical Storm Warning is now in
effect for Ngulu and Yap islands. Tropical Storm conditions are
expected within the next 24 hours. If 30W deviates further south,
the island of Kayangel in Palau could see increasing winds, while
a deviation further north could increase the threat to Ulithi and
Fais in western Yap State. For more information on TD 30W, see
bulletins, advisories and warnings issued by the Joint Typhoon
Warning Center under WMO header WTPN31 PGTW, and by the National
Weather Service under WMO header WTPQ31 PGUM and WTPQ81 PGUM.

&&

.Eastern Micronesia...
A trade-wind disturbance embedded within fresh trades will
maintain periodic showers near Chuuk thru Thursday morning, and
Pohnpei until late this evening. Then drier northeasterly trades
should provide fair weather for Pohnpei on Thursday, and Chuuk by
Thursday evening. Farther east, a surface trough is progressing
westward near Kosrae and the Marshall Islands. This feature will
prolong wetness near Kosrae thru Thursday evening, and Majuro
until late Friday afternoon. This same feature will probably bring
more wet weather to Pohnpei by Thursday night, and Chuuk near
Friday night. After the passage of this feature across the entire
area, drier northeasterly trades should once again promote fairer
weather near Majuro and Kosrae toward this weekend, Pohnpei and
Chuuk early next week. Latest ASCAT and Visible satellite imagery
reveals another trade disturbance associated with surging trades east
of the Date Line near 158W. This system might introduce more
showery weather and gusty winds for the entire region from east
to west next week.

Persistent trade-wind swell and wind waves will prolong hazardous
surf across Chuuk, Pohnpei and Kosrae States thru this weekend.
Seas near Chuuk and Pohnpei will also remain hazardous for small
craft operation thru this weekend.

&&

.Western Micronesia...
Discussion for the Chuuk forecast can be found under the Eastern
Micronesia section above.

Tropical Depression 30W has formed southeast of Yap near 6N142E
this evening. TD 30W is expected to strengthen and will likely
become a tropical storm late tonight. The latest forecast track
brings it just south of Yap near Ngulu around noon Thursday.
Based on the wind field from HR ASCAT satellite imagery, damaging
winds will spread over Yap by mid morning Thursday and will
continue thru mid afternoon. Once 30W has moved west of Yap by
early Thursday evening, winds should decrease noticeably. Deep
convection west and north of the depression center will also
impact Yap with possible locally torrential rain from later
tonight thru Thursday afternoon. An overall rainfall of 3 to 5
inches is possible by Thursday evening. With Koror being farther
away to the southwest, the weaker south side of 30W will pass
north of the capital. Therefore, no damaging winds are expected
there; mainly moderate to fresh winds thru Thursday night. Modest
convergence near the south side of 30W can still trigger periodic
heavy showers and thunderstorms but no torrential rain is
anticipated. Once 30W has moved into the Philippine Sea on Friday,
both winds and shower coverage should decrease across both places.
During the weekend, a weak surface ridge in the wake of 30W might
provide partly cloudy skies for the area.

Swell and wind waves produced by Tropical Depression 30W will
continue to impact Yap and Koror thru Thursday evening. Expect
very rough seas and very high surf near both locations, especially
near Yap thru Thursday afternoon before gradually subsiding
starting Thursday night. Coastal inundation of 1 to 2 feet is also
possible on Yap during the high of this event.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...High Surf Advisory until 6 PM CHST Saturday for GUZ001>005.

Marianas Waters...Small Craft Advisory until 6 PM CHST Saturday for
     PMZ151>154.

&&

Kleeschulte/Chan

Event by event

1 tropical storm. Local standard time, as filed.

Tropical Storm, Micronesia

When
December 22, 12:00 AM GST to December 24, 12:00 AM GST
Where
Micronesia forecast zone
Property damage
$100,000
Crop damage
$50,000
Reported by
Official NWS Observations

Surface analysis on the morning of the 20th indicated a circulation roughly 375 miles southwest of Chuuk and 700 miles southeast of Yap. The circulation became better organized over the next 36 hours finally becoming Tropical Depression 30W on the evening of the 21th. At that time it was 270 miles southeast of Yap.

On the morning of the 22nd the depression strengthened to Tropical Storm Nock-ten. At that time the tropical storm was located 135 miles to the southeast of Yap Island.

Nock-ten passed about 15 miles west-southwest of Yap during the late afternoon of the 22nd. Maximum wind speeds near the center of the tropical storm was around 45 mph. Observations from Yap during the day showed winds gusting to between 30 and 35 mph during the afternoon and evening with the maximum gust to 37 mph.

Reports from Yap Island report minor damage across the island with small tree branches down and banana tree damage, otherwise no reports of injuries or significant damage.| |During the late afternoon, around 16:15 local time, on the 22nd damage was reported on Falalop Island, which is part of Ulithi Atoll in Yap State. At this time the tropical storm was about 140 miles south-southwest of Falalop.

Reports from the island indicate damage to many houses on the island. Many of these homes were just rebuilt following Typhoon Maysak, which passed the island in late March 2015. There was also damage to agricultural items with newly planted crops being uprooted. These plants are important for the islanders to live on. There were some thoughts that the damage was caused by a tornado, but the damage is more consistent with straight line winds. Satellite imagery shows an outer rainband from the tropical storm over the island. As the rainband passed over the island, downdrafts from some of the thunderstorms in the rainband may have caused the damage.

What these are

Tropical Storm
A tropical cyclone with sustained winds of 34 to 63 knots (39 to 73 mph).

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Guam in 2016Every state in 2016This day in weather historyWarnings in Guam, December 2016The 2016 hurricane season

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 678211.