Thursday, April 29, 2010

Philippines Update: The Weather Outside is Frightful

It rained last night in Metro Manila. Hard.

This was the first time in two months we've had rain. Does it signal a shift from the dry season to the rainy season?

When I look at an interactive map at, it appears so. There are prevailing westerlies to the south of the Phlippines, curling around and pulling humidity north and to the east--and bringing us rain.

But if it is, I certainly won't find out from the official weather service here. (More on that topic later.)

The Amihan and the Habagat
The March-to-May period is summertime in the Philippines. It's the hottest time of the year. Schools are out; they will resume in June.

The dry season runs from around November to May or June, when the prevailing wind is from the northeast, and the wet season from May or June to around November, when the prevailing wind is from the southwest.

The northeast seasonal wind is known as the Amihan, and the southwest seasonal wind is known as the Habagat.

The Amihan allegedly blows in cool air from as far north as Siberia, and I've seen the term "cold front" in describing a little pick-up in the breeze on certain days. It's a relative term. A cold front here is analogous to a fast snail or a quiet seventh-grader. Not very fast, not very quiet, not very cold.

This is not the Midwest, where the cold fronts form giant V-shaped wedges across hundreds of miles in the skies and come booming in with thunderheads, tornadoes, and 30-degree temperature drops. The cold fronts here might raise the prevailing breeze from 7 to 9mph and drop the temperature a degree, maybe two.

The irony of the Amihan season is that the end of it is the hottest time of the year, ie, now. Even in a hot place such as this, the summertime heat is remarkable.

So the heat has been building steadily for six weeks now. Each day seems incrementally warmer than the last. Typical high-low readings are 95/75, 97/73, 95/73, 99/77, etc.

Everybody in the US knows about humidity and its effect on hot weather. They're a little less sure about where it's humid, but they know high humidity makes things miserable. When I lived in the East for awhile, people asked me if it was humid back in my native Midwest. People in the Midwest wonder the same thing about the East.

Affirmative for both regions.

Now that I'm spending a lot of time in Southeast Asia, trying to get a grip on business outsourcing on the one hand and cloud computing on the other, people from the US have asked me if it's humid here.

Yes, it is. I live at approximately 14.5 degrees north latitude. The tropics kick in somewhere around 22 or 23. We're hundreds of miles below the tropical line. So it's humid.

This is an El Ninyo year, which in this part of the world means drought. Hydroelectric power has been crippled, leading to numerous blackouts, some of them lasting throughout the daylight hours.

With the drought comes an unrelenting sun, the kind you can imagine in an old Clint Eastwood western, or more appropriately, in any movie about India. Heat and Dust meets the Good, the Bad, and the Ugly.

Very few people venture out between 9am and sunset at 5pm. The few that do are usually women after a kilo or two of rice, or perhaps some gossip; they carry lovely, delicate parasols. The guys who have to work in the sun (and it's mostly men), whether in construction, installation, or driving a tricycle, wear towels and other garmets to protect their heads from boiling over.

Then, last night, it rained. Clouds had been building a bit over the past couple of days, in our area centered around the volcanic Mt. Arayat, which rises out of the Pampangan plains. Yesterday, they seemed to be reaching a critical mass, and by nightfall, all hell finally broke loose. Thunder, lightning, moderately high winds, and precipitation by the bucketful.

The temperature dropped noticeably; for the first time anyone could remember, it felt cool.

Weather Nuttery: It's Important
I'm a weather nut, clearly. Most Midwesterners are, because there's a real good chance that the weather will kill you there over the course of any given year. So you better learn about it, know the forecast, and use your own sense and experience to make your own real-time forecast.

I grew up listening to 10-minute weather discussions on TV, full of isobars, dewpoints, wind chills, occluded fronts, precipitation probabilities, and all the rest. I know the difference between a thunderstorm (or tornado) watch and a warning.

There's a government agency, Pagasa (Philippine Atmospheric, Geophysical, and Astronomical Services Administration) that forecasts the weather.

But Pagasa (the word coincidentally means "hope" in tagalog) is just a damned bureaucracy. The Philippines is highly centralized, bureaucratic country (thank-you, Spain), and Pagasa fits right in.

Even though the agency has very high expertise in observing and describing atmospheric conditions, ie, the weather, it is focused only on its "area of responsibility" and very, very laconic in making predictions.

Pagasa was chastised last year when what appeared to be just another typhoon suddenly ballooned into Ondoy, flooded large parts of Manila, killed several hundred people, and made tens of thousands of others homeless.

I remember on another occasion when a tropical disturbance turned into a moderate-sized typhoon shortly after Pagasa warned only of an "increased southwest flow."

But Pagasa is typical of the way things are done in this country. People are given rules to follow, they follow them, and there is no advantage--no upside, as we say in Silicon Valley--in sticking your neck out and offering an opinion. This is a serious weakness of this country, that hampers its efforts to compete globally with its more aggressive neighbors, but that's a different story.

Returning to the topic of typhoons, they come from the east, striking the relatively unpopulated areas of the Philippines first. Manila is on the western edge of Central Luzon island, so is usually spared the worst of the storms.

The seeming discrepancy between the prevailing southwest winds in typhoon season and the typhoons' actual approach from the east lies in simple geography. During typhoon season, the prevailing winds in Southeast Asia are from the east, but travel under the southern Philippines, then curl up and to the right to manifest themselves as southwesterlies.

Pagasa knows all this, and more. Check out the wind-analysis graphic I picked up from its website. Looks like it was created by smart people to me:

So why in hell isn't anyone from there telling me about all this rain? It's raining again today, this time in mid-afternoon. But my visit to the Pagasa website states the following:

"Low Pressure Advisory: The Low Pressure Area was estimated at 350 kms Northwest of Puerto Princesa City (12.5°N 116.5°E)."

To be fair, elsewhere on the site it tells me that conditions in the metro area "will be partly cloudy to cloudy with isolated rainshowers or thunderstorms mostly in the afternoon or evening."

But where's the rest of the story? I see precipitation all over the little Bing weather map at, something that I haven't seen for two months? Where did this come from?

The dewpoint jumped up about 7 degrees today, compared to the last several weeks. Where is Pagasa's commentary on that? Where's the passion, dude?

More important, does this storm signify the shift from Amihan to Habagat? This often happens in a single day? Has it this time? Has the monsoon occurred? Is typhoon season upon us?


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