Storm Forecasting in the Western Pacific

Old Weather Watcher
Still an Old Weather Watcher

As an unbiased  observer (and retired Weather Person) living on Samar Island, I find myself tuning in to forecasts generated by ALL regional agencies here in the Western Pacific. Tropical storm forecasting has always been a tricky business, even so today with all the latest technology at ones disposal. As a old-time employee of the U.S. Navy’s Guam Fleet Weather Center and Joint Typhoon Warning Center (JTWC), I spent a total of 5 years on Guam and accumulated another 3 years of actual  at-sea storm evasion experience based out of Cubi Point here in the Philippines. I can say for the most  part I grew up and was weened (weather-wise) on western  pacific tropical weather  systems. I do stay tuned in closely  when need be, and  sometimes when the outlook for an approaching storm looks bleak, I find myself taking a more proactive role and will summon up my own prognostication skills (old school as they may be), and can assimilate my own feel-good forecast based on our location and orientation in relation to the storm’s track. If anyone reading this can take anything away from this article, it should be that while all regional meteorological agencies do have their own stand-alone capabilities, they do inspect and confer upon other agency products, generally speaking. The one exception to this might be PAGASA, as they more than likely purchase much of their raw data and satellite services from other nations.


To many cooks spoil the brew!
To many cooks spoil the brew!

On of the inherent problems with forecasting in the Western Pacific Basin is the fact that there are multiple agencies each generating their own storm forecasts for their areas of responsibility. Once the warnings are published, they become entangled together created by a mix of social media outlays. Because there is so much data being shared across many platforms, once it reaches the public there is no telling where the original message came from or how convoluted it might have become. This creates havock with emergency management agencies trying to keep things under control in their own areas of responsibility in check.  And whether things go good or go bad, someone will always be left barking loudly about the lack of advance notice and or misinformation received in untimely fashion, when in reality, if they would have only listened to the official information put out by the congnizant authority, there wouldn’t be so much confusion. For example, back in early December of 2014 we experienced an onslaught by Super Typhoon Hagupit (renamed by the Philippines authority PAGASA as Ruby) and was the second most intense tropical storm of 2014 (next to Typhoon Vongfong). There were many credits taken for forecast accuracy (mostly after the fact), and as many discredits given, to the forecasting abilities of some of other well-known players in the business. To make the statement (as some will claim) that PAGASA was more accurate with this storm as compared to all the other agencies is pure nonsense. I for one, and being a full-time resident of Samar, took a specific interest in constructing my own forecast for Typhoon Hagupit and I can in all honesty say in retrospect after looking at the storm’s historical data and track, and after comparing all agencies, that the U.S. Navy’s Joint Typhoon Warning Center (JTWC) had Ruby’s track nailed consistently and early on from the beginning. Because of their early accuracy, I leaned more heavily on their models as compared to the others. There was little variance in forecast to position accuracy for about the first 4 days (little variance meaning the storm’s position remains well inside the cone of error), until the storm approached the coast of Northeastern Samar. (One must keep in mind that PAGASA does not get involved with generating any warnings until the storm enters the Philippines Area of Responsibility (PAR), at which time they will also rename the internationally assigned name.

Super Typhoon Hagupit (Ruby)
Super Typhoon Hagupit (Ruby)

Once Hagupit entered the PAR, both the Japanese Meteorological Agency (JMA) and PAGASA in the beginning were way off target with their westward forecast tracks indicating a path of intended movement well to the south across southern portions of the Visayas. JMA and PAGASA however adjusted their tracks late in the approach of the storm (well after entering the PAR) to better coincide with JTWC’s outlooks. When the storm eventually took a left turn, only then did PAGASA appear to be in the drivers seat-position late, to take some undeserved credit.when Hagupit took her equator-ward turn. I likened this entire forecasting scenario of typhoon Hagupit to dropping a race car onto a racetrack late in the race with a fresh motor, new driver, a full tank of gas and four new tires. It is much easier to appear to get things right when in the “nowcast” mode vs. the “forecast” mode. PAGASA has a history of inconsistency and late forecast issuance and also have been known to miss an entire forecast period without an update on storms…for reasons unknown. Take the latest storm Typhoon Mekkhala (Amang); PAGASA never took this storm to typhoon strength while all other agencies upgraded it to typhoon strength (verified) . This stand alone attitude is not only reckless and dangerous, but rather arrogant. While nothing higher that Signal Two was issued for Samar with Typhoon Amang (who once again took the brunt of another storm) the many residents here seem to be totally dissatisfied with PAGASA’s overall performance.

Left turn...hello Samar!
  Left turn…hello Samar!

 Ask any resident here (Calbayog City) which storm was  worse (Yolanda, Ruby or Amang) and you will get Amang  as the answer, even though Calbayogon’s witnessed a  direct hit with Ruby. As long as the public receives their  information from and through multiple sources, the  public’s  perception of incompetence will continue. I should also  point out  that while JTWC  had a good handle on Typhoon  Hagupit  for example…from  it’s inception, they fell on their  sword late and just before she turned and decided to pay  us a  close-up and personal  visit. The bottom line here is  there is no single agency that stands above the rest, they equally all have both good and  bad storm forecast histories. They each have their own area of responsibility. However, with PAGASA using and sharing many of the technologies of providers such as JMA, the United States (JTWC), Hong Kong, and Korea, they should learn to pool their resources and give credit where credit is due. And that goes for all concerned.

In addition to all official agencies that forecast in the Western Pacific region, another good source of information that I have come to use is the independent forecasting and advisory group called Western Pacific Weather (you can visit their website here). They do a good job in interpreting and assimilating all available products of all competing agencies – and tell it like they see it. 

Per meteorologist Robert Speta with Western Pacific Weather, “One thing that drives me crazy is the fact that there are to many agencies on one storm in East Asia. This is a fundamental problem that goes back many years but given globalization of the world today one would think the western pacific basin would have one agency for everywhere. (Technically that’s JMA, but every country still issues their own, even America gets involved.) Every other basin does not have this problem. WMO states JMA is the official Regional Specialized Meteorological Center (RSMC) but your local agency can issue local warnings. So AT THIS TIME the official warnings are JMA and PAGASA.” (Speaking to storms affecting the Philippines.)

Just like the International Space Agency has become a combined effort, it’s time for the global meteorological community to lean on the World Meteorological Organization (WMO) for sound leadership and more consistent member integration of products and services. Maybe with better leadership, at least at a minimum, we wouldn’t have a minimum of three different names for every storm that comes our way. 

One caveat about JTWC, they do carry a “Products and Services Notice” on their site that reads:
“This is a U.S. government website. JTWC products on this website are intended for use by U.S. government agencies. Please consult your national meteorological agency or the appropriate World Me
teorological Organization Regional Specialized Meteorological Center for tropical cyclone products pertinent to your country, region and/or local area.”  Read the complete notice here.

Naval Meterology
Naval Meteorology

In closing, I will advise that anyone living in the Philippines should  pay particular attention to the JMA and finally PAGASA, as they  are the official RSMC’s for this area.

 Even though I am retired now in Samar, I can still practice one  thing for certain when it comes to out-guessing any approaching  storm…that will be keeping my double-headed coin polished and  ready and I will always be prepared for the worst because when  it comes to storm forecasting, you either get it right or you got it      wrong. There is no in-between!