Chris Scott Said:
"The 1430 METAR would report the highest gust since the previous report, i.e., 45 kts. So I doubt the surface W/V gusted to 70 kts either before. or after, the approach we are discussing."
Gust included in METAR is the maximum instantaneus speed reported in the last 10 minutes. WMO standard defines a gust as the maximum wind speed exceeding the "mean speed" by 5 m/s (10 knots) during the 10-minute interval.
So the 1430 METAR in my opinion will never indicate any gust produced before 1420, and so on...