Archive | August 24, 2011

23 UTC August 24, 2011 (August 25, 2011 Japan) Typhoon Nanmadol Update

Nanmadol (Bagyong Mina) continues to intensify and is now a typhoon according to the JTWC. Maximum sustained winds are now at 120kph gusting to 150kph. Nanmadol/Mina continues to move westward at a very slow pace of 5kph. Mina was last located approximately 340km northeast of Virac, Catanduanes or about 330km east of Casiguran, Aurora.

Latest and earliest Visual Satellite Imagery for August 25, 2011 (Image from NRLMRY):


Latest microwave image is now showing an established eyewall. This feature is now beginning to be visible on the satellite. We do expect further intensification due to the very warm waters east of Luzon. Wind shear continues to be light (around 10kts).

Microwave image from NRLMRY

Rains continue to be well offshore of the Philippines, despite the continued westward movement. High surf and violent seas will, however, continue affecting the eastern seaboard of Luzon including Cagayan Aurora, Isabela, Quezon, Polilio Island, and the Bicol Region. There could be occasional rains and gusty winds due to some outer rainbands making their way from Nanmadol’s huge circulation.

Computer model forecasts continue to diverge significantly but I am becoming more confident on the following scenario: Typhoon Nanmadol will continue drifting east of Luzon. It is possible it will be close enough to the Philippines on Thursday that Signal Warning #1 might be needed. Rainfall amounts could be around 50-100mm.

By Thursday, it should begin turning northward as a cyclone developing west of the Marianas strengthens (Invest 97W). This future storm will then influence Nanmadol’s track. There is increasing chance that Taiwan and Okinawa will feel some tropical storm conditions beginning Saturday. The exact track, however, is still up in the air. As I said, this will all depend on a developing system outside the PAR. Latest VIS and IR Image now showing a very huge cloud circulation with banding now occurring. It is possible that this system will be upgraded to a tropical depression tonight.

Please stay tuned for the latest update. We will have another update by around 12pm today. Hopefully, I will be able to put up a video by this afternoon; I apologize for not having done one yesterday.

Always stay tuned for updates from me, Rob, and Brian.

-WxCaster PAT

TCFA 97W/ Tropical Depression Update / 25 AUG 2011

The area of convection to the North West of Guam is still foretasted to get it’s act together today, the Joint Typhoon Warning Center in Pearl Harbor has re-issued there Tropical Cyclone formation alert on the system as they are still expecting it to develop.

Many indicators are pointing towards the likely hood of a typhoon to come out of this system, starting with a broad area of circulation already embedded within the widespread convection around it, on top of that wind shear remains relatively low through the entire region.  This combined with optimum sea surface temperatures makes for decent chance of development.

Due to it developing later than originally intended it may very well head off to the North East and away from any landmass and away from Tropical Storm Nammadol. This would cause less of a direct interaction with the two, good news is that it will make the storms easier to forecast, bad news is that they will not feed off of each other as much thus leading to larger storms. Kind of opposite of what people would think but it is usually the case.

But that is all for today, a quick update, I do want to note as have been for the last several days, this storm is still in it’s early states and due to the many factors in play here can be unpredictable. Therefore continue to check for updates and new forecast to be put out.

~Meteorologist Robert Speta

Tropical Storm Nanmadol (Mina) Update / 24 AUG 2011

Tropical Storm Nanmadol (Bagyong Mina) continues to intensify at a constant pace as it drifts across the Philippine Sea. It was last located approximately 400km northeast of Virac, Catanduanes or about 540km east of Casiguran, Aurora. Maximum sustained winds have increased to 100kph with gusts of up to 130kph. TS Nanmadol/Mina has been drifting to the west at around 5kph.

Latest Visual Satellite and IR Imagery show an improving circulation with flaring convection right over the center. Cloud tops continue to be cold (around -80C). Recent microwave images also suggest that an eye might be forming on the mid-level circulation. The low-level center, on the other hand, is still slightly displaced to the northeast. Nevertheless, we still expect this intensification to continue, albeit at slow pace.

The forecast for Nanmadol remains vague and uncertain as computer models continue to diverge and be inconsistent on their solutions. What is throwing the computers off is the possible direct-cyclone interaction of Fujiwhara effect this weekend between Nanmadol and a developing system northwest of Guam (Invest 97W). The trends tonight have actually lessened the effect of this DCI; some models actually take Nanmadol towards Taiwan!

Because of this, we have shifted our forecast track a little bit to the north. We now expect Nanmadol to continue moving northward longer than previously thought. We are still expecting this system to turn northeastward this weekend. Just a warning, though–we still have low confidence on this forecast track due to the numerous uncertainties regarding Nanmadol and 97W so please continue to stay with us for the latest updates and possible changes with the track. Obviously, anyone from Taiwan all the way to Kyushu/Shikoku needs to monitor this storm constantly. The projected timing (if it hits any of the areas mentioned) would be Sunday or Monday so we still have time to adjust the track accordingly.

~Text written by WXCASTER PAT at http://www.sagitnangbagyo.blogspot.com.