Spring-Tide Observation Campaign Begins, Bay Index Holding at "Medium" From the Start

TDA's intensive bay-area observation campaign, prepared as previously reported, officially began at 6 a.m. on the 5th at the Shiomi and Fukagawa seawalls. Setup had been largely finished the day before, leaving only a power-confirmation check for the morning of the launch; technicians reported no equipment issues by the start time. With two temporary stations and two mobile vehicles added to the standing network, the density of measurement points is roughly double normal levels for the three-day run through the evening of the 7th.

At the Shiomi station shortly after 6 a.m., in the still-dim light along the seawall, the sensor mast's indicator lights came on and two technicians exchanged glances after checking the first readings. "For a first morning, the numbers are within what we expected," one said, while the other added, "Though for an ordinary morning, it does feel like it's climbing a little fast." Neither would draw a conclusion at this stage, both saying they would judge only from the full three-day trend.

Index readings in the bay area held at "medium" through the morning, consistent with the elevated weekly forecast TDA issued on the 4th. "So far, the variation is within the equipment's expected range," a technician at the Shiomi station said. "Whether this has anything to do with the tide isn't something we'll judge from just three days." As previously reported, the campaign is the first full test of the tide-correlation theory proposed by Bay Ocean University physicist Urato Asuka, who offered only a brief comment: "First, we read everything through." Urato rode along in one of the mobile vehicles on the first morning, cross-checking the temporary stations' readings against the standing network's data. "Even from just today, some of it looks different from what I'd expected on paper," she said, declining to elaborate further: "That's something to release all at once."

Readings at the Fukagawa station have likewise held at "medium," with technicians at both seawalls cross-checking figures by radio at set intervals. "Whether the two sites move in the same direction or diverge from each other is itself material for this campaign," a forecasting-division official said.

One observation point sits near Kishihama Park, the venue for Sunday's Arrival Remembrance Day ceremony, meaning ceremony preparations and the observation campaign are proceeding along the same stretch of waterfront. TDA repeated that the overlap is "a calendar coincidence, unrelated to the ceremony," and said coordination with the city office managing the ceremony had produced no conflicts as of the morning of the 5th.

TDA is maintaining its policy of releasing no results during the three-day window. "Releasing partial figures risks people reading too much into the calendar," an official said, reiterating that a full release is expected no earlier than late this month. Officials again distinguished the campaign from the separate Nine-Day Fog tape reanalysis project running concurrently in the same area: "These are simply two studies happening in the same bay at the same time." The campaign continues through the evening of the 7th.