Weather Center: Guam

Current alerts

1 typhoon warning, 1 coastal flood warning and 1 high surf warning touch Guam. 1 typhoon warning 1 coastal flood warning 1 high surf warning (touching Guam)

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NWS alerts checked 04:05Z · Data: NOAA/NWS

Sources & update times

SPC Day 1 outlook issued 00:50Z · Data: NOAA/SPC

SPC Day 2 outlook issued 16 Oct 17:24Z · Data: NOAA/SPC

SPC Day 3 outlook issued 16 Oct 19:22Z · Data: NOAA/SPC

SPC discussions checked 04:05Z · Data: NOAA/SPC

SPC storm reports checked 04:05Z · Data: NOAA/SPC

WPC Day 1 outlook issued 00:56Z · Data: NOAA/WPC

WPC Day 2 outlook issued 16 Oct 19:17Z · Data: NOAA/WPC

WPC Day 3 outlook issued 16 Oct 19:17Z · Data: NOAA/WPC

Each feed is judged on its own clock. The masthead’s reading is the site’s publishing health, which is a different thing: a publishing delay does not make a freshly read warning stale, and a fresh check does not make an old outlook newly issued.

NWS warnings / WPC selected forecast: feeds current

NWS warnings: Feed current; checked 04:05Z.

WPC selected forecast: Feed current; checked 04:05Z.

Checked means retrieved, not newly issued. Each graphic retains its issue, observation, initialization or valid time. Site publishing status is separate.

Hazard & forecast product

WPC Day 3 Excessive Rainfall Outlook, Sunday 18 Oct

Source: WPC

Now, not forecast: Current warnings as of 04:05Z are drawn over the outlook for Sunday 18 Oct, the warnings hatched so the forecast shows through. They are in force now; the outlook is for its own period. Show the forecast alone

Forecast: WPC’s scale

1 · Marginal

View scale

1 · Marginal
2 · Slight (not outlined)
3 · Moderate (not outlined)
4 · High (not outlined)

WPC Day 3 Excessive Rainfall Outlook, valid 18 Oct 12:00Z to 19 Oct 12:00Z, issued 16 Oct 19:17Z · Data: NOAA/WPC. Warnings and watches are as of 04:05Z (now), not for the outlook’s period.Guam is outside this map, which draws the conterminous states; its warnings are listed below.

Everything on the map, as a list

WPC Day 3 Excessive Rainfall Outlook: Marginal

Briefing details · Where, When, Main hazards

Sunday briefing for Guam

Highest anywhere in Guam: no outlook here

This is the outlook, a forecast. Warnings in force here are listed above it and outrank it.

SPC and WPC issue outlooks for the lower 48 states only; Guam’s warnings are listed with the current alerts.

Where: Guam is outside the area SPC’s and WPC’s outlooks cover, the lower 48 states.
Prepare: Guam has no SPC or WPC outlook to prepare from; follow its warnings in Current alerts.

Official discussion

WPC’s discussion held was issued 00:58Z, and the map 16 Oct 19:17Z: they are different issuances, so the text is not shown with this map until the matching one is read.

WPC’s outlook page

Forecast details

The chance that rainfall exceeds flash flood guidance within 40 km (25 miles) of a point during the valid period, as WPC defines its categories. Marginal is at least 5%, Slight 15%, Moderate 40% and High 70%. WPC’s categories are separate from SPC’s severe-storm categories, and an outlook category is not a warning: a Flash Flood Warning means flooding is happening or imminent. WPC’s definitions.

Coming days · Guam

2026-10-17Severe storms: Outside lower-48 outlook coverageFlash flooding: Outside lower-48 outlook coverage 2026-10-17Severe storms: Outside lower-48 outlook coverageFlash flooding: Outside lower-48 outlook coverage 2026-10-18Severe storms: Outside lower-48 outlook coverageFlash flooding: Outside lower-48 outlook coverage

These are daily outlooks, not arrival times. Days 4–8 retain SPC’s predictability and potential-too-low wording in the dated outlook controls.

Severe storms

General thunderstorms at its highest nationally. SPC’s convective outlook, on its own scale.

View severe outlook

Recent reports

Reporting period: 12Z 16 Oct – 12Z 17 Oct

0 tornado · 0 wind · 0 hail in Guam

Preliminary reports: a count of reports, not of storms. None reported is not proof that nothing happened.

View reports: map, table & download

No watches or mesoscale discussions in Guam. Watches, discussions and warnings in the Live tracker

Warnings in Guam

3 warnings touching Guam

3 warnings touch Guam, most urgent first. A warning across a state line is counted here and in the other state.

NWS alerts checked 04:05Z · Data: NOAA/NWS

Since 03:06Z: no change in the warnings.

Warnings 3

Typhoon Guam Coastal Waters; Rota Coastal Waters; Guam; Rota until 20:00Z crosses Guam and Northern Mariana Islands Track: Typhoon Warning, Guam Coastal Waters; Rota Coastal Waters; Guam; Rota
Coastal flood Guam; Rota; Tinian; Saipan until 18 Oct 18:00Z crosses Guam and Northern Mariana Islands Track: Coastal Flood Warning, Guam; Rota; Tinian; Saipan
High surf Guam; Rota; Tinian; Saipan until 18 Oct 18:00Z crosses Guam and Northern Mariana Islands Track: High Surf Warning, Guam; Rota; Tinian; Saipan

All 3 warnings touching Guam, with their full text, in the Live tracker

55 warnings elsewhere in the country: the national list.

Not an official warning service. Warnings and watches are the National Weather Service’s, outlooks and reports the Storm Prediction Center’s and the Weather Prediction Center’s (Data: NOAA/NWS, NOAA/SPC, NOAA/WPC). When a warning is issued for you, act on it, and use weather.gov or a NOAA Weather Radio for where you are.

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