HONOLULU (HawaiiNewsNow) - Guillermo is headed toward Hawaii, but one of four radars used to track approaching storms isn't working right now.
So how does this impact forecasts, especially since there is now a strong chance of heavy rain?
There are four radars across the state of Hawaii. One on the South Point on the Big Island, one on the Windward side of the Big Island, one on Molokai and the fourth on Kauai. With the North Kohala Radar down, meteorologists now have to improvise.
"Just sort of extrapolate it out based on what the other radars are showing. Something's we may just have to make do with what we have, and we may not have the best information, but being able to see what's going on in other areas and sort of be able to fill in the gaps that way," said National Weather Service Meteorologist Matthew Foster.
The Doppler radar is a critical tool to forecast rain.
Meteorologists with the National Weather Service say about a month ago, the one along the Hamakua Coast went down for scheduled maintenance. It's scheduled to be completed on Wednesday, the same day Guillermo is expected to hit the islands.
So forecasters are heavily relying on other ways to track the storm's path, like "Hurricane Hunters".
"They are very critical in that they allow the forecasters to get some data that the satellites cannot quite do yet. That is exact center position, the strength of the winds at the surface, and where that track may be headed based on those data parameters that get put into the forecast models," said Maj. Kyle Larson, an aerial reconnaissance weather officer with the 53rd Weather Reconnaissance Squadron based at Keesler AFB in Mississippi.
On Sunday, Maj. Larson and other Hurricane Hunters flew into the eye of the storm. He said Guillermo is weaker than what was previously forecasted.
"A little bumpier as went through the eye as you can imagine, but otherwise, it's what we can expect for a cat 1 cat 2 type hurricane," he said.
Click here for the latest forecast on Guillermo: http://bit.ly/1gqc9v2
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