I'm not seeing an equivalent function in the weather.gov API

Since forecast-v3.weather.gov does have a 'search' capability, there is likely a way to do it, but it's just not documented about how to do it via the API itself.

The 'search' area on the page has some code                <form name="getForecast" id="getForecast" class="form-inline" action="/point" method="get">
    <div id="getfcst-body">
        <div id="loc-search-block">
            <input id="searchInput" name="q" type="text" class="form-control" placeholder="Location or Zip Code" autocomplete="off">
            <input id="btnSearch" name="" class="btn btn-default" type="submit" value="Go">
        </div>
        <div id="txtHelp" class="row">
            <a href="javascript:void(window.open('/bundles/noaatemplating/static/searchHelp.html?7958d2e','locsearchhelp','status=0,toolbar=0,location=0,menubar=0,directories=0,resizable=1,scrollbars=1,height=500,width=530').focus());">
                View Location Examples
            </a>
        </div>
    </div>
    <div id="searchOptions" class="hidden">
        <div id="useCurrent" class="search_option current_location">Use My Current Location</div>
        <div id="searchResults">
            <div id="searchResultsService" class="search_block hidden">
                <div class="search_option search_heading">Search Results</div>
                <div class="search_content"><div class="autocomplete-suggestions" style="position: absolute; display: none; max-height: 159px; z-index: 9999;"></div></div>
            </div>
            <div id="searchResultsHistory" class="search_block">
                <div class="search_option search_heading">Recent Searches</div>
                <div class="search_content"><div class="search_option saved_location">Cedar Rapids, Iowa</div><div class="search_option saved_location">Lufkin, Texas</div><div class="search_option saved_location">Minden, Texas</div><div class="search_option saved_location">Baldwin, Alabama</div><div class="search_option saved_location">Saratoga, California</div></div>
            </div>
            <div id="searchResultsMessage" class="search_block hidden">
                <div class="search_option search_heading">Notification</div>
                <div class="search_content"></div>
            </div>
        </div>
    </div>
</form> and is driven by JavaScript to do the listings/updates, likely with some currently undocumented query.

We've got a few months yet before the old www.weather.gov is cycled to the new format.

The closest I've been able to approximate this makes use of a file that converts zip codes to lat/long points.

https://github.com/jalbertbowden/us-data/tree/master/civicspace-zip-code-database

From that file, I generated a (big) PHP table indexed by zip code.  With the lat and long, a useful query can then be constructed to get meta data (forecast zone and NWS office) as well as the forecast.

I have code based on this running in my sandbox (not on my live site). Essentially I allow a "zip" URL parameter on the forecast page and monkey around with the variables that advforecast2 uses before including it.

Thanks,  I saw the reply .. it doesn't address the search capability (which is not in the current API per se).. the function of MapClick.php to provide a forecast is replaced by a series of API calls (point, gridpoint), but that doesn't provide the search using 'zipcity.php' on their site.. the https://www.weather.gov/documentation/ docs don't mention 'zipcity.php' as a function, so we won't know if it exists in the future.