Update: 10:00 p.m. ET: Typhoon Hagupit has weakened considerably from its monstrous 185 mile-per-hour intensity at this time on Wednesday. The U.S. Joint Typhoon Warning Center indicates the storm now has maximum sustained winds of about140 miles per hour, which is the equivalent of a Category 4 storm. Such a storm is still capable of doing major damage, but is not nearly on par with 2013's Super Typhoon Haiyan, which devastated much of the city of Tacloban in the Philippines.

The reason for the weakening is vertical wind shear that is disrupting part of the storm's circulation, and since this shear is likely (but not certain) to continue, the JTWC is forecasting additional weakening before landfall in northeastern Samar on Saturday. The center of the storm may come within 40 miles of the national capital of Manila on Sunday or Monday.

Update: 6:00 p.m. ET: Typhoon Hagupit may no longer be a super typhoon, as it appears significantly weaker based on satellite imagery alone. It is still a very intense storm that will be capable of causing major damage and loss of life, but it has likely fallen below Category 5 or high-end Category 4 status. At least for the time being...

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Super Typhoon Hagupit poses a major, life-threatening danger to the Philippines — including the same areas of Leyte and eastern Samar that were devastated by Super Typhoon Haiyan last year, and where nearly 100,000 families are still living in highly vulnerable makeshift shelters.

Making matters worse, residents of the central and northern parts of the archipelago are facing considerable forecast uncertainty, with the U.S. Joint Typhoon Warning Center predicting a slow, drenching crossing of northern areas, including a direct hit on the capital of Manila over the weekend.

Infrared satellite image of Super Typhoon Hagupit on Thursday, Dec. 4, 2014. Image: NOAA

However, the Philippines' own weather agency, known as PAGASA, as well as the Japanese Meteorological Agency and forecasters in Taiwan, are predicting the storm will head nearly due west, striking storm-weary islands of Samar and Leyte, including the city of Tacloban, which was nearly wiped off the map last year by Super Typhoon Haiyan.

See also: Incredible photos show a changed Philippines one year after Super Typhoon Haiyan

Here is what we know, and what is more uncertain, as of Thursday afternoon:

The typhoon peaked in strength overnight as a high-end Category 5 storm, and remains a Category 5 storm. It will likely slowly weaken as it approaches the Philippines, due to higher winds aloft that will disrupt the storm's inner circulation, like a hand disrupting the path of a spinning top on a flat surface, causing it to wobble off course and spin more slowly. In addition, the water temperatures near the Philippines are cooler than they are where the storm explosively intensified on Tuesday and Wednesday, and such storms are sustained by warm ocean waters. Hagupit is the fifth Category 5 storm in the Western Pacific in 2014, which is the first time that has happened since 1997. Climate projections show that by 2100, tropical cyclones in many ocean basins may be more intense, but less frequent, although the science on this is still evolving.

Estimates of the storm's strength at landfall range from a Category 2 to a Category 4 typhoon.

The storm will be moving slowly — at about 10 miles per hour — when it crosses the Philippines, which will mean extraordinarily high rainfall totals are possible. The Philippines is full of variable terrain, including volcanic peaks that have slopes vulnerable to landslides. Heavy rain may be the most significant threat this storm poses, both for urban areas and for rural locations.

Locations from eastern Samar to Manila need to prepare for a possible landfalling storm, which would bring flooding, storm surge and high winds starting on Saturday, local time, and lasting through the weekend (progressing slowly from the country's eastern to western parts).

Local governments have begun to issue evacuation orders for the most vulnerable areas, according to Joe Curry, the Philippines' relief coordinator for the Catholic Relief Services (CRS), who spoke to Mashable by phone from Manila on Thursday evening, local time. Curry said his organization has about 300 staff members in Leyte and Samar who are continuing to help residents of hard-hit Tacloban recover.

High resolution VIIRS satellite image of Super Typhoon Hagupit. Image: NOAA/NASA/RAMMB/CIRA

The uncertainty about the storm track is complicating storm preparations, he said. “The real messaging is happening from the local, municipal and city governments right now.” Evacuations are already occurring in parts of Tacloban and other areas in Leyte and Samar, according to Curry.

“We probably won’t know until tomorrow, Philippine time, what will be an accurate path for the storm,” he said. “Those staff and all of our equipment that’s been used for our recovery effort so far ... if a typhoon does hit those areas we will reallocate our resources to respond.”

Still lots of spread among agencies on track/timing of #Hagupit #RubyPH Central/Northern Philippines on high alert. pic.twitter.com/fRFAvM6KHC — Brandon Miller (@BrandonCNN) December 4, 2014

Yeb Saño, a commissioner for climate change for the Philippine government, told Mashable that the forecast scenarios offer only bad options.

“The scenarios are quite sobering considering that it would either plow through the same corridor that Haiyan took last year, or it would actually hit the national capital of Manila," he said in a Skype conversation. "Both scenarios are just unimaginable with a storm of this intensity, so we’re not leaving any stone unturned."

“It’s a challenge to find ourselves with this multiple scenarios that are quite divergent; even Super Typhoon Haiyan had a clear path about four days before landfall."

Saño gained international fame in 2013 after he made an emotional plea for international action to address climate change, following the destruction caused by Haiyan. But this year, he was mysteriously left off of the Philippines delegation to the climate talks, underway now in Lima, Peru, at the last minute.

Where am I? I am in my motherland, The Philippines. I stand with my people as we face another super typhoon. #YebNotInLima — Yeb Saño (@YebSano) December 4, 2014

“A lot of lessons have been learned in the last year since Haiyan, in empowering governments at the local level, and the local governments are a lot more prepared," Saño said, adding that the federal government's philosophy is to let local governments take the lead in preparing their residents for the storm.

Curry, of the CRS, said Super Typhoon Haiyan, which was known as Yolanda in the Philippines, taught local residents and his staff what the worst-case scenario would be in Leyte and Samar, including where to evacuate safely. The CRS has prepositioned relief items, including water sanitation and purification kits and emergency shelters, which could be sent to hard-hit areas quickly if necessary, Curry said.

If flooding is the biggest threat from the storm, which current forecasts suggest, it may be more difficult to get people to prepare, for two main reasons. First, Curry said rainfall amounts is "one thing we don’t predict well with typhoons.” And second, residents of the Philippines, who are accustomed to experiencing close encounters with as many as one dozen to two dozen tropical storms and typhoons per year, may be far more aware of the danger of storm surge flooding after Haiyan, and could underestimate the flood threat from heavy rainfall.

"Last year, people didn’t take it seriously. People stayed to secure homes and other assets because of concern of what would happen if they leave the house," Curry said, adding that “these are poor families for the most part,” and their homes are their biggest asset.

One thing that is different this year, though, compared to the pre-Haiyan environment is that there are already many humanitarian agencies in Tacloban, including the CRS. In addition, there is greater vulnerability, since 95,000 families are still living in makeshift shelters there.

“Hopefully they’ll be evacuated, but what they’ll have when they return we don’t know,” he said.